Saltash and Lynher Valley circular walk
  1. Make your way out of the car park and turn left onto the road. Follow this beneath the bridges to an area with a pier.

    A ferry operated at Saltash between Cornwall and Devon from mediaeval times until the 20th Century. It is thought initially it would have been operated by opportunistic fishermen, ferrying passengers bound for the monastery at St Germans. Records from the 12th Century indicate that by this point it was owned by the manor of Trematon. The ferry finally ceased in 1961 when the suspension bridge was opened.

    During the Second World War, the US navy opened a base at Saltash in 1943 for repairing and maintaining landing craft. The strips of iron which can be seen along the waterfront when the tide is out are the remains of a series of sloping piers. These were used to beach boats at high tide which were worked on when the tide fell.

  2. Bear left onto the pier and then follow the waterside path with benches to reach the Union Inn.

    The building with 1595 on the front was formerly the Boatman Inn, originally known as the Passage Inn due to its proximity to the ferry.

    Parts of the core of the building date from the sixteenth century, but the façade is mid-nineteenth century. It used to include an archway crossing Tamar Street but this was destroyed as part of the 1957 "slum clearance" scheme which involved demolishing most of the waterside historic buildings, some others of which dated from the 16th Century.

    During the early 19th Century, Ann Glanville was married to a waterman (who rowed passengers across the Tamar). When her husband fell ill, she took over his place in the boat. After much practice from rowing every day to feed her children (who ultimately numbered 14), she put together a 4 woman crew and competed in regattas. She achieved national fame. Her winning of a race against an all-male crew was watched by Queen Victoria who personally congratulated her.

  3. Pass the inn then turn right and walk a few paces to a junction with Tamar Street. Turn left and walk a short distance uphill to another junction with Culver Road, with a signpost for Mary Newman's Cottage

    The Union Inn is thought to date from Victorian times. Sometime around the 1860s it was licensed to William Odgers - a Cornish seaman awarded a Victoria Cross who became landlord when he retired. After Odgers died in 1873, the building was also recorded as the Union Inn on the first edition OS map from the 1880s.

    Previously, it had a simple white front with "Union Inn" painted above the door. The striking painting of the Union flag was added in 1995 to celebrate the 50th Anniversary of VE Day. Despite a few initial complaints from the other side of the Tamar, the flag design has become an icon, earning a place in books such as "The strangest pubs in Britain" and now gets repainted when needed. The mural on the right side of the building depicts the history of Saltash.

  4. Turn left into Culver Road and follow it past Mary Newman's cottage. Follow the road uphill to reach a junction on the left with a postbox.

    Mary Newman's cottage is so called because it was said to be the home/birthplace of Sir Francis Drake's first wife although there is no direct evidence for this. Francis Drake married Mary Newman in 1569 at St Budeaux and a year later, Francis Drake is recorded as living in Plymouth (presumably with his wife). His cousin married a man from Saltash so it's also possible that there were other family connections with the cottage. Using the treasure, reward and investments from his circumnavigation, Drake purchased a large number of properties in the Plymouth area so it's also possible that the cottage could just have been part of his property empire but no evidence has so far been found to support this. The building has been dated to the 16th Century but could contain some earlier mediaeval elements.

    More about the cottage and Mary Newman.

  5. Turn left onto Coombe Road and follow the road through the tunnel under the railway then continue downhill to the bottom of the valley to cross the stream and reach a path beside a sign on the right for Coombe Woods.

    Francis Drake was a farmer's son from Tavistock who began a career as a mariner when his family moved to Kent. His cousins, the Hawkins family, were from Plymouth and Drake moved back to the southwest to work for them. During his twenties he made three trips to the Americas to trade with the Spanish plantation owners but was attacked by Spanish warships on the final voyage and only escaped by swimming.

  6. Turn right and follow the path uphill into the woods to reach a junction of paths with a post marked "Lenny's Lane".

    Unlike their more versatile narrow-leaved cousins the three-cornered leeks, ramsons grow mainly in shady places such as woodland. Their broad leaves are solar panels that have evolved to capture the weak winter light early in the year before the trees are in leaf. They are an indicator that woodland is ancient and has provided a shady environment over a long period to colonise.

    Black fungi that resemble lumps of coal are known as coal fungus but also King Alfred cakes due to a legendary baking disaster by the regent. The dried fungus can be used with a flint as a fire starter - a spark will ignite the inside which glows like a piece of charcoal and can be used to light dry grass. There is evidence that prehistoric nomadic tribes used glowing pieces of fungus to transport fire to a new camp.

  7. Bear right at the Lenny's Lane marker and follow the path down the steps and over a bridge to reach posts for Lenny's Lane and Megan's Way.

    The word "fairy" comes from an older English word faerie which itself is from the Old French faierie meaning "realm of the fays" (similar to modern French patisserie being along the lines of "realm of the cake maker").

    faie was an Old French Romantic term for a woman skilled with magic or herbs. The alternative English word for fairy - fay - comes directly from this.

  8. Bear right onto Megan's Way and follow the path to a post at the top of some steps marking Megan's Way and Izzy Coo Park.

    Daffodils contain chemical compounds which are toxic to dogs, cats and humans and ingestion of any part of a daffodil is likely to cause a stomach upset e.g. when unsupervised children have eaten leaves. The bulbs have both higher concentrations and a broader range of toxins than the rest of the plant and can be mistaken for onions (although don't smell of onion).

    Squirrels are rodents, closely related to chipmunks and slightly more distantly to dormice. The word "squirrel" originates from an ancient Greek word meaning "shadow-tailed", referring to the bushy tail of a squirrel. A family group of squirrels is known as a "drey" (also the word for a squirrel nest). A group of unrelated squirrels is known as a "scurry", though squirrels tend not to hang out in groups.

  9. At the junction at the top of the steps, turn right and follow the path to reach a sign for Eva's Bridge.

    Bracket fungi are one of the most important groups of fungi responsible for wood decay. This is good for nutrient cycling but less good if you own a forestry plantation. Many bracket fungi begin on living trees and can eventually kill a branch or whole tree by damaging the heartwood and allowing rot to set in. They can continue to live on the dead wood afterwards and a much more diverse range of species of bracket fungi are found in old natural forests with lots of dead wood.

  10. At the Eva's Bridge post, bear left and follow the path to reach a junction of paths marked Lottie's Lane and Stream Path.

    The jay is a member of the crow family recognisable by the flash of electric blue on their otherwise brown body. Their natural habitat is woodland, particularly oak.

    Like squirrels, jays collect and bury acorns as a winter food store. Once jays were the main means by which oaks colonised new locations as a population of 65 jays can bury (but not always find again afterwards) half a million acorns in a month. Jays prefer to bury their acorns in open ground which is an ideal spot for a new oak tree.

  11. At the junction, turn left onto Lottie's Lane and follow this uphill to a junction of paths. At the top, turn right and follow the path past a post for Phil's Close and out of the woods to reach a junction of paths

    Celandine roots have numerous knobbly tubers and when these break off, a new plant can regrow from the tuber. Digging animals such as rabbits and squirrels can therefore help to spread celandines. In some parts of the world they have become an invasive problem where their dense mat of leaves chokes out native species which have not evolved to compete with them.

    The rate at which a tree grows varies through the year depending on the amount of light and moisture available. This is visible in a sawn tree trunk as a ring where the wider lighter area wood is laid down more quickly in spring-early summer and then the narrow darker area more slowly in late summer-autumn. Each ring corresponds to a year and so the age of the tree can be worked out by counting the rings.

  12. Turn left and follow the path to emerge in a cul-de-sac and follow the road a few paces to a junction with a Prouse Rise sign.

    Following his marriage, Francis Drake worked as a privateer conducting raids on Spanish ports in central America where gold and silver artefacts seized from the natives by Spanish colonists were being shipped back to Spain.

  13. Turn left and follow the left pavement of the road uphill to another junction (beside a Chichester Crescent sign).

    In 1577, Drake was tasked by Queen Elizabeth I with a secret mission to intercept Spanish ships carrying gold and jewels on the western side of South America. This was spectacularly successful - capturing many tons of treasure - far more than expected. As Spanish warships would block his return, the plan was to sail onward up the west coast to Alaska and return through an uncharted "north west passage" to the Atlantic. When Drake reached Alaska, he couldn't find an obvious way through the maze of large islands so was forced to carry on west towards Japan and, by accident, became the first Englishman to circumnavigate the globe.

  14. Keep left to follow the pavement uphill towards another junction and continue on the path along the front of Spencer Gardens. Cross over the Spencer Gardens road to join the pavement along Lynher Drive. Keep following this, crossing any junctions leading into residential estates, until you reach the one into The Rivers, opposite a school.

    On returning with huge amounts of treasure from his circumnavigation voyage, Drake was paid £20,000 plus personal gifts and also received a 4700% return on the money he had invested in the voyage. Overnight be became one of the wealthiest men in England and invested some of this in property in Plymouth (and possibly also Saltash).

  15. Turn right to cross the road and follow the school entrance road a few paces to a path on the right just after the No Stopping sign just before the school gates. Join the path and follow this until it eventually ends in a metal barrier next to a sign about Wearde Camp.

    Drake used his wealth charitably, helping friends and family financially and also funding public projects such as a leat system to bring clean drinking water to Plymouth from Dartmoor. Many generous deeds are documented including gifts to released prisoners. Drake served as a town councillor and mayor and fortified Plymouth against attack from possible Spanish raids.

  16. Continue ahead onto the lane and follow it to a bend with a junction.

    To the left of the lane, and the fields ahead are the start of the River Lynher section of the Tamar Valley Area of Outstanding Natural Beauty.

    The Tamar Valley Area of Outstanding Natural Beauty has a similar conservation status to a National Park. It encompasses an area of 75 square miles around the rivers Tamar, Tavy and Lynher, partly in Cornwall and partly in Devon. This also includes an area of Cornwall and West Devon mining landscape World Heritage Site, 41 county wildlife sites and over 1700 hectares of woodland. It was first suggested in 1963 that the Tamar valley area should be designated but this was only eventually granted in 1995.

  17. Follow the pavement a few paces around the bend to the right then cross to the entrance gate to Churchtown Farm nature reserve. Once through the gate, take the path to the left to reach a junction of paths as you exit the field.

    Cornwall Wildlife Trust was founded in 1962 as the Cornwall Naturalists' Trust and was run entirely by volunteers until 1974. It was renamed in 1994 as part of a national initiative to unify the names of wildlife trusts across the country. It now manages over 50 nature reserves and has over 17,000 members with over 1,000 active volunteers.

    There's a volunteering section on the Cornwall Wildlife Trust website which includes lots of marine activities as well as things in the nature reserves.

  18. Turn left to enter the field on the left. Once in the field, head initially for the gateway in the middle of the hedge opposite, but as you approach, bear right to follow the path along the top of the bank to where it crosses over the hedge on the right.

    The dandelion-like flowers along the coast are most likely to be catsear, also known as false dandelion. Catsear is very salt tolerant, not only growing along the coast but actually in sand dunes. The easiest way to recognise it is by the hairy leaves, hence the name. If you can cope with the texture, the leaves are edible and are much less bitter than dandelion leaves.

    Another way to tell them apart is when they are flowering. Although dandelion flowers over quite a long period, the most profuse flowering is in April and May whereas catsear's intense flowering period is in late June and through July. Catsear has neater flowers than dandelion with squarer edges to the petals (but still toothed). The stems supporting the flowers are also solid, in contrast with the hollow stem of the dandelion.

    The River Lynher (pronounced "liner", as in ocean) is just over 20 miles long, rising on Bodmin Moor and joining the Tamar in its estuary near Saltash. The name dates back to mediaeval times, being recorded as "Lyner" in 1318. It is also known as the St Germans River at the point where it widens into a broad, tidal channel, close to its mouth.

    During Victorian times, the river was polluted by copper mining waste and during the late 20th century, runoff from intensive dairy farming and an increase in arable farming were found to be affecting water quality and silting the gravel beds needed by spawning salmon. In the early 21st century, a number of these issues were addressed under the Cornwall Rivers Project.

    The river is now a haven for wildlife with several stretches being designated as Sites of Special Scientific interest (SSSIs). The river's resident species include otters, brown trout and Atlantic salmon which breed in its major tributary, the Tiddy.

  19. Follow the path up onto the hedge and down the steps and through a gate. Once in the field, stick to the main path which starts parallel to the right hedge then gradually bends to the left (ignore the stile on the right). Continue on the path, aiming for the well-worn section by the hedge to reach a kissing gate.

    The castle that you can see to the right is Trematon.

    The castle at Trematon is thought to have originally been one with motte and bailey design and is referred to in the Domesday book. In the 12th Century, this was rebuilt with a stone keep surrounded by a stone wall (known as a curtain wall). In the 16th Century, the keep was a ruin and was used a jail. However even in 1750, overall it was described as "the most entire castle of its sort in Cornwall". In 1807, a large Georgian house was built where the bailey originally was and large sections of the curtain wall were demolished and removed as this interfered with the view.

  20. Go through the gate and down the steps to a track. Turn right and follow the track over the bridge to where a small path departs to the left immediately after the metal post in the centre of the track.
  21. Bear left down the steps and follow the path to meet the bottom hedge. Follow along the bottom hedge (you can optionally walk along the top of the beach then return to the path on the far side). Continue to the corner of the field where the path passes over some tree roots.

    A cordial can be made from blackthorn blossom by dissolving 100g of sugar in 1 litre of warm water mixing one large handful of blossom, scaled up to produce the quantity you require.

    Lichens often grow on sick or dying trees so some gardeners assume that the lichen might be harming the tree. In fact, it's purely because these trees have fewer leaves so there is more light available for the algae inside the fungus to photosynthesise. It's too dark under many healthy trees for the lichen to grow.

  22. Cross over the tree roots then duck under the tree trunk. Climb up the bedrock into the field then bear left slightly towards the river to meet the bottom hedge and follow along this to reach a path leading through the bushes onto the riverbank.

    Skylarks are the most common member of the lark family in Britain and are often known simply as "larks".

    During mediaeval times, skylarks were eaten and there are records of the food price for larks from the 13th Century onward. Larks were captured by dragging nets across fields at night, not unlike modern commercial fishing techniques.

  23. Bear right to stay in the field and head uphill slightly from the corner of the hedge to bypass the grassy area to the left. Continue to meet the left hedge where the path passes to the left of a small tree.

    The muddy shore of the Tamar provides a habitat for invertebrates such as ragworm.

    Ragworm live in burrows in muddy seabeds and get their name from their feathery row of legs either side which make them look a bit like millipedes. They spin a mucus net from their burrow to catch whatever small thing floats past. They live for around a couple of years, spawn once and then die but each female can produce a million eggs. Consequently they are very abundant and an important food for wading birds. They are cooked and eaten in China and considered a delicacy in Vietnam.

  24. After the tree, continue straight ahead to pass the bench then keep following parallel to the left hedge to reach a wooden post with a blue waymark just before a stile, and a gap in the wall to the left of the post.

    The walled area of water on the creek is the remains of a tidal mill, used to grind corn. The mill building is dated 1613 and fell out of use as a mill in the 1860s. It has since been converted into a house.

  25. Bear left through the gap in the wall to the left of the post and then once in the next field bear left to head towards the viaduct. Keep walking parallel to the left hedge to turn a corner and when you can see a waymark post in the left hedge then head to this.

    Quite a few of the trees along the left side of the field are elder.

    Elder trees were associated with witchcraft which may have arisen because their berries were used in medicines. Consequently there were many superstitions about cutting down or burning elder trees.

    Elder be ye Lady's tree, burn it not or cursed ye'll be.
  26. Follow the narrow path leading from the post down into the woods and over the roots of a tree to reach a bridge over a small stream. Cross this and follow the path to emerge into a small field.

    Green woodpeckers are the largest and most colourful of the woodpeckers native to Britain and have a distinctive laughing "yaffle" call. The two species of spotted woodpecker are smaller and usually noticed from the drumming sound they make on trees although they can sometimes be heard making a short "cheep" sound. They are quite shy of humans but can sometimes be seen on garden bird feeders containing fat balls or peanuts.

  27. Follow the path along the left side of the field to where it re-enters the woods.

    Dandelions are dispersed very effectively by the wind. The tiny parachute-like seeds can travel around five miles. Each plant can live for about 10 years and produces several thousand seeds each year.

    Despite their native habitat being woodland, wood pigeons are able to thrive wherever there is food. They have fared better than most birds with intensively-farmed crops and are particularly fond of oil seed rape. They are able to hoover up food quickly (up to 100 pecks per minute) and stuff large amounts into their crop (e.g. around 150 acorns!). They then digest this overnight.

  28. Follow the path into the bushes and keep right to follow the path up the steps and beneath the viaduct to a kissing gate.

    The Forder Viaduct carrying the Great Western main line was opened in 1908 when the route was diverted further inland from the original Cornwall Railway route. The new section of railway ran through the settlement of Wearde and so was given the name the "Wearde Deviation"!

  29. Go through the gate and follow the path along the left side of the field to where it re-enters the bushes.

    The main line railway through Cornwall was originally conceived as a means to link the port of Falmouth to London. However, whilst funds were being raised for the railway, much of Falmouth's Packet trade was transferred to Southampton. The line was built to Truro instead but initially failed to make money and was bought up by Great Western. Once established, the new railway allowed rapid exports of perishables to London including fresh flowers and fish. It also made large-scale tourism possible and the term "Cornish Riviera" was coined.

  30. Follow the path to a kissing gate and go through this then follow the woodland path near the water's edge until you reach a Churchtown Farm information board before the path descends to the foreshore.

    The spore from a fern doesn't grow into a fern. Instead it grows into an organism resembling a liverwort (i.e. a small green blob). Instead of producing spores, these produce eggs and also sperm which they interchange with neighbouring blobs to get a new mix of genes. The fertilised egg grows into a new fern and so this alternating process of ferns and blobs repeats.

  31. Follow the path onto the shore and follow along this to reach a gravel track in front of some houses.

    Sea purslane (Halimione portulacoides - Americans call a different plant "sea purslane") grows along estuary mudflats and is immediately recognisable by its grey-green leaves forming a large carpet near the high tide line. The greyness of the leaves is partly due to tiny hairs which reflect sunlight to reduce water loss. It's also due to salt expelled through special glands in the leaves drying on the surface.

    Sea purslane leaves are edible (and often feature on Masterchef amongst "sea vegetables"). They are very salty when raw, but when cooked this diminishes to more mellow levels. They turn bitter if overcooked, so a short dunk is ideal. The young, green leaves are the most tender which are most abundant in late spring/early summer.

  32. Continue ahead on the gravel waterside track which eventually becomes tarmacked and follow this to a junction with the road.

    In the 18th Century, a limekiln was built beside the creek at Forder and there is some evidence of small-scale quarrying for limestone that might coincide with this. From the 1860s until well into the 20th Century, limestone quarries operated on a more intensive scale. By 1906, a rock crusher plant had been set up, linked by a tramway to the quarries. Quays with loading chutes were also built along the creek and connected to the tramway. The crushed rock was exported as far as London and Holland. The remains of the chutes are still visible.

  33. Turn right and follow the road uphill to a junction with St Stephen's Hill.

    In July 1581, the Spanish Armada was spotted off The Lizard, fire beacons alerted London and an English fleet was hastily assembled at Plymouth. The more manoeuvrable English ships were then able to bombard the Armada ships from a distance with cannon fire but the Spanish fleet was larger and organised into a defensive formation. After some skirmishes in the Channel, the Armada anchored off Calais in their formation. Drake sent in fireships and although none of the Armada ships were burned, most cut their anchor cables and broke formation. The English were then able to target the less well-defended ships with cannon fire. The Armada was chased up the east coast of England and Scotland and was forced to sail around the top of Scotland to the west side of Ireland where their leaking hulls and lack of anchors proved fatal as they were driven onto the rocks by the winter storms. Ultimately they were beaten by the British weather.

  34. Turn right onto St Stephen's Hill and follow this to the entrance to St Stephen's church.

    During winter, from November to March, winter heliotrope is visible along the edges of roads and paths as carpets of rounded heart-shaped leaves.

    The leaf shape of winter heliotrope is similar to its close relative butterbur, but the leaf edges are more rounded than butterbur and the leaves are evergreen whereas butterbur puts up flowers before it has any leaves. Both plants spread via rhizomes (underground stems) and their broad leaves can crowd out other plants making them potentially invasive.

  35. If you don't have a dog, enter the churchyard and follow the path around the right-hand side of the church (keeping the church on your left) to reach an arch (lychgate) with a path leaving the churchyard on the far side and follow this to emerge on a road. Dogs should instead be taken along the pavement to reach the exit from the churchyard.

    The first record of the church of St Stephen is from 1269 and it's thought to have been founded in Norman times by the landowning family in Trematon Castle. Most of the church is now from the 15th Century although there is some Norman stonework remaining at the base of the tower and the font is also Norman. The church underwent a Victorian restoration in 1872. A flower bed just outside the church is thought to be a font bowl from late mediaeval times. There is also a mediaeval Gothic lantern cross which was previously in the grounds of the vicarage.

  36. Turn right onto the road and follow the pavement (crossing over Rashleigh Avenue) to a junction with Wearde Road, signposted to the community college.

    The story that Francis Drake insisted in finishing his game of bowls before defeating the Spanish Armada is now thought to be an Elizabethan urban myth. The true delay in the launch of the English fleet is thought to be due to adverse weather conditions and currents. The story is recorded in print only 37 years after the event.

  37. Carefully cross over Wearde Road and then join the narrow road with no-through signs. Follow this until it ends in a junction.

    Drake continued raids on Spanish ports into his mid-50s and eventually died of dysentery (which was common in the tropics). He was buried at sea in full armour in a lead-lined coffin which divers are still searching for.

  38. Continue ahead to the roundabout and cross over Beatrice Avenue to follow St Stephens Road downhill. Keep following the pavement (crossing over any junctions) to reach a roundabout at the far end of the road.

    In 1969, a government report was published that recommended that South East Cornwall should be removed from Cornwall County Council and combined into a Plymouth unitary authority. This was not well-received by the Cornish and there were threats of the Tamar bridge being blockaded. A referendum was held in Saltash on whether it should be part of Plymouth which was rejected by an overwhelming majority of over 84%. Following a general election and change of government in 1970, the idea was abandoned.

    There's more info including some amusing illustrations on the Saltash website

  39. Cross over King Edward Road to join Fore Street and follow this downhill to a bend and junction with a smaller road continuing ahead downhill.

    After the Norman Conquest, the castle and manor of Trematon was held by Robert of Mortain who took the market away from the monastery of St Germans and re-established it closer-by at Saltash. A borough was formed in the 12th Century and, as well as having a market, Saltash was the only licensed sea port between Fowey and Dartmouth. There was a town gate at the west end of Fore Street during medieval times. By 1377, it had 200 tax payers.

    In 1201, Saltash was recorded as Burgh de Esse. In Norman times, the name Esse seems to be associated with places called Ash (there are still quite a places called Ash dotted around England), in many cases due to a Norman landowning family called Esse. The settlement at Saltash was known for a while just as Ash. The "Salt" (a reference to the estuary location) was added later to distinguish it from all the other places called Ash. The 1584 Charter states that Essa is now commonly called Saltash.

  40. Join the narrow road leading downhill and follow it most of the way down the hill to where a path on the left with three black bollards passes beneath the bridge.

    Originally, Brunel had planned a twin track viaduct carrying wooden sleepers to cross the Tamar but this was rejected by the Admiralty as they thought the 100 ft arches with 80ft clearance would be too restrictive for shipping. A second revision with 300ft spans and higher clearance was still rejected with a stipulation that there should only be a single pier in the water to support the bridge. Brunel was forced to go for a lightweight design supporting just a single track, using wrought iron in place of timber sleepers to hold the track.

    Work began in 1854 on the first of the two main trusses but the shipbuilding company contracted to build it went bankrupt before completing it. Under Brunel's instruction, the Cornwall Railway company used their own workforce to complete the truss for the Cornwall side and one for the Devon side was more successfully subcontracted. The trusses were tested extensively on the land by hanging them with weights before they were moved into place. The completed bridge was finally opened by Prince Albert on 2 May 1859. Brunel only just lived to see it opened as he died later that year. The bridge carries his name at either end as a memorial.

  41. Turn left onto the path with the bollards and follow this beneath the bridge then uphill through some trees. Keep left to emerge in a grassy area with a large cross.

    During the 1950s, it became clear that a better road link was needed from Plymouth to Cornwall. After much lobbying of the UK national government, Cornwall County Council and Plymouth City Council finally gave up and formed a joint committee to build a bridge themselves, using a toll to recoup the building cost of £1.5 million. Work began in 1959 and the suspension bridge was unofficially opened in October 1961.

    In the 1990s it was found that the bridge's 1950s design was unable to support the European Union weight requirement for goods vehicles. So, between 1998 and 2001, the bridge was strengthened and widened at a cost of approximately £35 million, using funding from the toll charges. On a busy weekday, the bridge is used by over 50,000 vehicles.

    More about the Tamar crossings

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  42. Continue across the gravel to emerge onto a lane on the far side, opposite the Air Training Corps building.

    Scholars speculate that the Celtic Cross (a crucifix with a circular ring) developed from the sun cross (a cross inside a circle), a common symbol in artefacts of Prehistoric Europe, particularly during the Neolithic to Bronze Age periods. When Christianity came to the Celtic regions, Christians extended the bottom spoke of this familiar symbol, to remind them of the cross on which their new Saviour was crucified.

  43. Turn right and follow the road a short distance downhill to a bend then bear right onto the path leading from this and follow it downhill. Keep following the path downhill to where it ends on the road via some metal barriers and bear right to cross the road via the pedestrian crossing to return to the car park and complete the circular walk.

    Plymouth grew from the mediaeval waterside village of Sutton to a port town by Tudor times and continued to grow throughout the Industrial Revolution. The three neighbouring towns of Stonehouse, Devonport and Plymouth were formally combined as the city of Plymouth in 1914. The city expanded further in the 1960s after post-war rebuilding of the bombed-out centre and incorporated Plympton and Plymstock. In the 2011 census, it was the 30th largest urban area in the UK.

Two species of seahorse live in Plymouth Sound (spiny seahorse and long-snouted seahorse). They hide in the sea grass which they grasp with their tails and live on a diet of shrimps and small crabs (of which they can eat around 30 a day!). Seahorses are famous for the males being the gender to brood the eggs within their bodies until they hatch as baby seahorses. They do this within a pouch, a little bit like that in female marsupials.

Sea beet is also known as "wild spinach" and is the ancestor of sugar beet, beetroot and Swiss chard. It can be eaten raw or cooked. The leaves are at their best during March and April and become tougher as the year goes on.

Sea beet has been cross-bred with domesticated crops to re-introduce some of the disease resistance from the tougher wild plant that were lost in the domesticated plants. It is also able to withstand quite high sodium levels in the soil which allows it to grow in salty conditions on the coast.

The name Tamar is documented in the second century and likely to be substantially older. It is thought it might share a common origin with the River Thames and both might stem from an ancient Celtic word meaning "dark". The source of the river is within 4 miles of the North Cornish Coast and the river flows 61 miles south across the peninsula forming the majority of the historic border with Devon. Work is being done by the Environment Agency to improve the water quality of the Tamar and its tributaries by reducing the amount of run-off of phosphate fertilisers into the rivers.

The word crow is from the Old English crawe. Since this sounds a lot like the noise the bird makes, there is a misconception that the Old English is directly derived from this. In fact the word is far older. It's related the the Old Saxon kraia and can be traced back further to a Proto-Indo-European word from the late Neolithic period which is thought to mean "to call hoarsely".

The word "crow" is sometimes used to refer to the whole crow family (including jackdaws, rooks and ravens) and sometimes specifically to the common (carrion) crow. Carrion crows can be distinguished from their cousins by being totally black (jackdaws have grey heads, rooks have pale beaks) and having a slender and fairly straight beak (i.e. not the broad beak with a hooked top that a raven has). Biologists use the word "corvids" for "crow family" to avoid ambiguity, or to show off.

The collective noun for a group of crows is a "murder". The term has been traced back to around the 15th Century, originally as a murthre (which was a Middle English word that meant "murder"). It is thought that the expression may be based on crows scavenging carcasses.

Birds of the crow family are considered to be among the world's most intelligent animals, displaying a high learning ability and are able to use logic for solving problems. Researchers have found some crow species capable of not only tool use but also tool construction. Crows have also demonstrated the ability to distinguish individual humans apart by recognising facial features. If a crow encounters a cruel human, it can also teach other crows how to identify that individual.

Research has shown that crows have a much higher density of neurons in their forebrains than primates do (the density of neurons in this region is thought to correlate with intelligence).

The brain of a crow accounts for 2.7 percent of the bird's overall weight whereas an adult human's brain represents 1.9 percent of their body weight. This is even more impressive when considered in context: birds need to be as light as possible in order to fly.

Ravens are considered the most intelligent crow species, outperforming chimpanzees in some tests. Consequently an academic is quoted as saying that crows are "smarter than many undergraduates, but probably not as smart as ravens."

Studies have shown that crows are capable of self-discipline. If offered one piece of food now or two later, the crows will resist temptation and wait. However if the initial piece of food is a high value item such as sausage, they won't take the risk.

Crows are omnivores and their ability to eat anything from animal feed to potato chips has allowed them to capitalise on food sources created by humans. Their problem-solving skills also allow them to access food that less savvy animals cannot, for example tugging on bin liners and tucking each fold under their feet to raise the contents of waste bins in motorway service stations.

Crows have a vocabulary of different calls with specific meanings and these can be varied to convey emotion like a human tone of voice.

The sounds that crows make have also been found to vary with location rather like regional accents in humans. When a crow moves into a new area, it mimics the calls of the most dominant flock members to fit in with its peer group.

There is a somewhat brutal rural tradition of hanging dead crows in fields with crops. Scientists now understand why this was so effective. Research has shown that crows understand the concept of death and can distinguish an (obviously) dead crow from a taxidermically-stuffed (alive-looking) crow. Crows often gather around a dead individual in "crow funerals" to try to determine the cause of death and assess the threat to themselves. They become wary of the place a dead crow is found but will also harass humans who handle crow corpses.

In the 3rd Century BC, the Romans named their ill-fated gangplank for boarding other ships "corvus" (Latin for crow) because its end contained a large metal spike which was thought to resemble a crow's beak. The end of the gangplank was dropped from a height onto the captured ship and the spike acted as a nail, attaching the gangplank to the deck of the ship being boarded. The design was short-lived because the 36ft gangplank sticking up from the front mast of the ship did nothing for its stability and consequently resulted in almost two entire fleets being lost in rough seas.

The magpie is a member of the crow family and like other crows is omnivorous, feeding on pretty much anything it can find although it prefers high energy foods. Magpies spend most of their life in a 6 mile radius of where they were born and live in loose social groups. They will form gangs and use complex social strategies for hunting and tackling predators. Names for a group of magpies include a "tiding", "charm" and "chatter" (the latter reflecting their social communication).

The magpie is believed to be one of the most intelligent of all animals. The area of its brain used for higher cognitive function is approximately the same in its relative size as in chimpanzees and humans. Magpies can count, imitate human voices, recognise themselves in a mirror and have been observed regularly using tools to keep their cages clean. It has even been suggested that magpies may feel complex emotions, including grief.

Since members of the crow family will eat the eggs and chicks of other birds, there has been concern that magpies might have an effect on the songbird population. However, an extensive study by the British Trust for Ornithology using 35 years of data found that the presence of magpies appeared to have no measurable effect on songbird numbers. It is thought that availability of food and suitable nesting sites are probably the main factors limiting songbird populations. Hedgerows are a particularly important habitat.

The folklore about magpies collecting shiny objects has been shown to be an incorrect myth. A scientific study found that magpies are actually scared of shiny objects and actively avoid them.

Even up to the 16th Century, magpies were simply known as "pies" from the Old French word pie (related to the Latin word for magpie - pica). The term "pied" meaning "black-and-white" (as in pied wagtail) is from the magpie's colouration. It's also possible that the pastry thing we now know as a pie (which can be traced back to Mediaeval Latin) was named after the magpie. It has been speculated that the assortment of ingredients in the pastry crust was likened to objects collected in a magpie nest. The "mag" in the modern name is a (somewhat sexist) mediaeval slang word for someone who chatters, based on the name Margaret.

A tidal mill is an ancient form of tidal power based on a water mill. As the tide comes in, it enters a reservoir created for the mill through a one way gate, which closes automatically when the tide begins to fall. When the tide is low enough, the stored water can be released to turn a water wheel.

In 1602, tide mills were described by Richard Carew in his Survey of Cornwall:

Amongst other commodities afforded by the sea, the inhabitants make use of divers his creekes for grist mills, by thwarting a banke from side to side, in which a flood-gate is placed, with two leaves; these the flowing tide openeth, and, after full sea, the waight of the ebb closeth fast, which no other force can doe: and so the imprisoned water payeth the ransome of driving an under sheete (i.e. undershot) wheel for his enlargement.

In 1919, Oscar Hartzell, son of a farmer in Iowa, contacted many Americans in the mid-west who had the surname Drake. He claimed that he was a distant relative of Sir Francis Drake and had discovered that the estate had never been paid to his heirs, that it had gathered interest for the last 300 years, included the whole city of Plymouth, and that it was now worth $100 billion. Hartzell invited investment in his campaign to sue the British government and assured everyone a return of $500 for every dollar they invested. Approximately 70,000-100,000 Americans sponsored him - some with all the money they had. Meanwhile Hartzell had moved to London and was living an opulent lifestyle whilst claiming he was negotiating with the authorities. This continued until authorities seized assets of some of Hartzell's agents' and they revealed the scam. Hartzell was not convicted until a copy of Drake's will was brought to his fraud trial in 1933, and he died in a prison hospital ten years later. Many of his victims believed in him to the end of their own lives.

The stretch of the estuary from the confluence of the Lynher and Tamar is known as the Hamoaze. This was recorded in 1558 as ryver of Hamose and is thought originally just referred to a creek that led to the manor of Ham which was located north of where Devonport Dockyard is today. The "ose" part of the name may derive from the Old English word wāse (meaning "mud") which is the origin of the English word "ooze".

In tidal rivers, the discharge of freshwater and friction with the riverbed effectively "holds back" the rising tide. The further up the tidal region of the river, the shorter the interval between low and high tide and the faster the rising tide comes in when it eventually does.