Hayle Valley circular walk from St Erth

From the car park, head to the Give Way sign and turn left. Cross the bridge to reach a bridleway sign, where a small path also departs towards the river. Turn left onto the riverside path and follow it for about half a mile to where a bridge for vehicles crosses the river.

St Erth is named after St Erc who was one of the many Irish who brought Christianity to Cornwall in the Dark Ages. The village is situated on what was the main crossing point on the River Hayle before the causeway was built in 1825. During the mediaeval period, the Star Inn was built as a stopover for horses and coaches and tin mined on the West Penwith peninsula was carted East along the road through St Erth. However the roads in Cornwall were notorious for being so badly potholed that carts or coaches could disappear into them, so long-distance haulage was generally done by ship from the ports along both coasts.
Pass the bridge and continue along the right-hand bank for another half-mile until you reach a wooden footbridge crossing a small stream cutting through the bank.

The Hayle River is 12 miles long and has its source near Crowan. The river's course initially runs west for 5 miles into what was once the lagoon separating Penwith from the mainland when sea levels were higher. The river then follows this valley north for the remainder of its course. The river flows through a number of old mining sites and consequently there are quite high concentrations of metals in the water. The river and the settlement near its mouth get their name from the Cornish word for estuary.
Cross the footbridge and continue a little further along the right bank until you reach a concrete footbridge crossing the main river.

You may see some small trout as you walk along the river.

Dissolved metals are normally toxic to trout but there is evidence that the brown trout population in the Hayle river has evolved to be able to cope with the high mineral levels in the water. A gene responsible for the production of a protein which detoxifies metals was found to be highly expressed in the Hayle river population and other proteins were found that bind and transport iron (one of the most common metals leeching from the mines).
Cross the bridge and follow the path to emerge onto a lane. Turn left and follow the lane for just under half a mile. Continue past the cottages to the top of the hill to reach a lay-by on the right opposite a track on your left.

Elder trees overhang the path along the river.

Elderflowers appear in late May and are easily recognisable as large white umbels on the shrubby green trees. If you are harvesting the flowers to make cordial or wine, avoid picking umbels where the flowers are going brown or haven't opened yet; they should be bright white with a yellow centre.
Turn left onto the track and follow it past several field entrances until the main track forks.

To make elderflower cordial, remove the bitter stems from about a 20 flower heads and soak overnight in 1 litre of water containing the juice of 2 lemons. Strain the liquid and dissolve around 600g sugar to make a sweet cordial. To make dissolving the sugar easier, you can pre-dissolve the sugar in the water in advance by boiling the water and allowing it to cool before adding the elderflowers although you lose some of your sugar on the discarded elderflowers that way. Dilute with water or sparkling water to serve. It can be frozen for use at other times of the year.
Keep right at the fork and continue a short distance to reach a waymarked field entrance on the right.

To make Elderflower wine, make a slightly lower sugar elderflower cordial in enough quantity to fill a demijohn and ferment with a white wine or ideally champagne yeast. By varying the amount of sugar from about 1kg to 1.5kg to a gallon of liquid, you can create either a dry or sweet wine, or with a champagne yeast, a very strong wine. The wine needs a little ageing to become less rough, but less than many fruit wines - a year is typically adequate.

To create a sparkling wine, make a dry wine and rack the wine into 2 litre plastic bottles with a small amount of airspace and add half a teaspoon of sugar - this is enough to generate some carbon dioxide and, unlike glass wine bottles, the plastic bottles are able to withstand the pressure. Don't use more sugar or completely fill your bottles with liquid or you risk an explosion. In this case, ageing of 6 months to a year is generally adequate.

Too much pollen from the flowers can make the wine bitter and murky yellow. Pre-washing the elderflowers before de-stalking and soaking them will remove some of the pollen as well as any creatures hiding in the flowers.
Turn right through the waymarked opening and follow the right hedge to reach a path in the far right corner.

You may well find the fields here planted with cereal crops such as wheat and barley.

Barley was one of the first domesticated crops and has been dated back over 10,000 years. Consequently beer made from barley is likely to have been one of the first alcoholic drinks consumed by the Neolithic tribes.
Bear right down the path and follow this through the woods to reach a junction of paths beside a wooden gate on the left.

The mixture of farmland and woodland in this area supports a population of stoats.

Stoats and weasels are related to badgers and to otters, which they more closely resemble. The stoat is roughly twice the size of a weasel but can be distinguished without the need to measure it by its black-tipped tail. The weasel preys mostly on voles, but the stoat will take on prey much larger than itself including birds and even full-grown rabbits. During the winter, the coat of the stoat (and also some populations of weasel) changes colour from brown to white to camouflage it in the snow.

The soft, silky winter fur of the stoat is known as ermine and garments made from this were a luxury associated with royalty and high status. Given that stoats mark their territory using pungent anal scent glands, it’s likely a fair amount of washing of the furs occurred before being draped over royalty.
Keep left to pass the gate on the left and join a small path. Continue on this past one bypassed stile to reach another into a field. Cross the stile into the field and turn right. Follow the hedge to the gate marked "Free Range Chickens".

Chickens are descended from junglefowl and those in Britain came originally from India. They evolved the ability to lay large numbers of eggs to take advantage of gluts of food that occur in their native forests. It is thought they were introduced to Britain by Iron Age tribes who bred them for fighting rather than meat and cockfighting remained Britain's national sport until 1835. During the mediaeval period, more placid forms of chicken were bred that were less hazardous to farm but it wasn't until the 17th Century that chickens and eggs were farmed on a mass scale. In Britain, over 10 billion eggs are now consumed every year.
Turn left and follow the path between the posts to reach a track running along the bottom of the field.

During a period of global warming before the Pliocene period (up to about 3 million years ago), rising sea levels flooded the dunes, turning West Penwith into an island. The Hayle valley was a narrow gulf separating the island from the mainland and the shallow sea depositing a layer of blue clay on top of the sand in the lagoons along the valley. As the climate cooled, sea levels dropped as water was tied up in the polar ice sheets, reuniting the island of West Penwith with the rest of Cornwall.
Turn right onto the track and follow this to reach the lowest area in the field, shortly before the track goes through an opening into the next field. As you round the bend at the bottom of the field, start looking out (easily missed!) for a small path leading off to the left into the woodland.

Fleabane grows in the field margins next to the track.

Common fleabane grows in damp areas and produces shin-height flowers resembling a large yellow daisy during July and August.

The leaves have a scent reminiscent of carbolic acid (phenol). The plant was therefore thought to be an insect repellent without too much thought given to what pollinates it. It was kept in houses in the hope of driving away fleas, hence the name. The genus name also derives from the Latin word for flea.
Bear left onto the small path (leading under a tree) into the woods and follow it until it emerges onto a lane.

If the footpath here is starting to get overgrown, let the Cormac Countryside team know (using the menu next to the direction then Direction Issue > Footpath Issue) and they can alert the parish council.
Turn right onto the lane and follow this back to the church to complete the circular route.

The fishing lakes along the river, known as "The Dixies", were once opencast mines and were worked during the Second World War by Prisoners of War, based at a camp in St Erth. They also built the pump house, next to the church, to feed water into their camp and the rest of the village.