Trebarwith Valley Circular Walk
- Distance:2.75 miles/4.25 km
- Walk grade:Moderate
- Start from:Trewarmett
- Recommended footwear:waterproof boots
- Pretty wooded valley at Jeffrey's Pit
- Views over Trebarwith Valley and Trewarmett Downs
- Views over Trebarwith Valley from Fentafriddle
- Pretty stream along the valley floor
- Trebarwith Nature Reserve
- Views back across Trebarwith Valley from Treknow
- At the telephone box, bear right down the small lane and follow this until it rejoins the main road at the top of Trewarmett Hill.
- At the junction, turn right and walk down the right-hand side of Trewarmett Hill, on the pavement where available, to reach the junction to Trebarwith Strand.
The engine house on the top of the hill on your left was part of the Prince of Wales Quarry.
Cornwall's iconic engine houses were built to house huge beam engines - a type of steam engine with a pivoting beam. This configuration was particularly suited to powering pumps to stop the quarry pits and mines from flooding as water trickled into them from above. Inside the engine house, steam from a boiler would push up a piston, causing the beam to tilt downwards, pushing the pump down into the shaft. The steam would then be shut off and cold water would be used to condense the steam within the piston back into water, creating a partial vacuum. Atmospheric pressure then pushed the piston back down into the vacuum, raising the beam and lifting water out of the shaft. The valves to apply the steam and cold water were mechanically automated, maintaining a steady rocking motion of the giant beam.
The engine house in Trewarmett is the only one preserved in North Cornwall. It was built in 1870 and the beam engine, installed in 1871, was used to drive a wire ropeway to haul slate, as well as pumping water out the quarry pit (which is now a lake). You can safely wander around inside (there are grilles covering the pit which once contained the beam engine).
- At the bottom of the hill, bear right to stay on the path and follow it alongside the road to Trebarwith Strand then after about 100 metres, cross the road into the parking area at Jeffrey's Pit.
Jeffrey's Pit, located at the top of the road to Trebarwith Strand, is an old slate quarry and was still working in the early 20th century, closing in 1928. Alf Burrell, who lived in Trewarmett and died in the 1970s, started work there as a boy, making tea using the water from the stream. The cutting sheds were on the opposite side of the road (now a house), and as you walk down the road to the beach, the slate tips are walled up on your right. The slate tips cover the stream, which re-emerges below them to continue its path down the valley.
- Walk up the left-hand side of the stream from the parking area, past the waymark and through the picnic area, to reach the woods.
- Follow the path into the woods, which follows the stream up the valley. Continue on the path up a short incline past an old flight of concrete steps to where path climbs in a long incline up a steep bank.
Upstream of Jeffrey's Pit, at the top of Trebarwith Valley, the public footpath runs for a 15-20 minute walk alongside the stream through ancient woodland. Few people go up here, so it's a peaceful spot and a good place to see wildlife. In early spring, you're likely to see frogs breeding in the stream. In April and May, the woodland floor is carpeted in bluebells contrasted by brilliant celandine, primroses and delicate wood sorrel flowers - an indicator that this has been under woodland for a long time.
- When you reach the steep bank, climb up carefully as this can be slippery in wet weather. Follow the path from the top of the bank, past a walled quarry pit on your left, until the path crosses through the stream.
Some estimates suggest the UK has up to half of the world's total bluebell population; nowhere else in the world do they grow in such abundance. However, the poor bluebell faces a number of threats including climate change and hybridisation from garden plants. In the past, there has also been large-scale unsustainable removal of bulbs for sale although it is now a criminal offence to remove the bulbs of wild bluebells.
- Cross the stream to the opposite bank then turn left along the path. Keep right along the path, following it uphill to a kissing gate into a field.
- Go through the kissing gate and climb the steep field, following the left hedge to the top corner.
In August, blackberries start to ripen on brambles. Blackberries are closely related to raspberries and technically neither is a berry but an aggregate of many individual tiny fruits, each containing a tiny stone like a miniature cherry. Blackberries are high in vitamin C, K and antioxidants. The seeds, despite being a bit crunchy, contain omega-3 and -6 fatty acids and further enhance blackberries' "superfood" status.
According to folklore, you should not pick blackberries after Michealmas Day (11th October) as this is when the devil claims them. The basis for this is thought to be the potentially toxic moulds which can develop on the blackberries in the cooler, wetter weather.
- Go through the rightmost of the gates, into the farmyard, and bear left to the gate next to the barn.
Trenowth Farm is from the Cornish word noweth and means "new farm". The term is somewhat relative as it dates back to mediaeval times, being recorded as Trenewyth in 1327.
- Go through the gate next to the barn. Follow the track, keeping right until it ends in a T-junction onto a lane.
The buildings over the hedge ahead are part of Trebarwith Road Rustic Quarry.
Trebarwith Road Rustic Quarry is located on the road from Delabole to Trebarwith village. The quarry was originally known as "Jenkins Quarry" and reopened in the 1990s under the new name. As well as rustic slate, Blue Elvan is also quarried here.
Elvan is very hard volcanic rock formed where magma intruded into other rocks to form a (vertical) dyke or (horizontal) sill that cooled fairly quickly, resulting in fairly small crystals. Chemically it is very similar to Granite, but in the case of Granite, slower cooling resulted in large crystals. Elvans can be seen in many of the churches across Cornwall where it is often used for intricate parts of buildings, such as doorways, so they can be finely carved.
The term "Greenstone" is used by quarrymen to describe igneous rocks that, unlike granite, are rich in iron and magnesium and these give it a blue-green colour. When Greenstone is formed as a sill or dyke it is sometimes called "Blue Elvan". This is also quite common in Cornwall and has been quarried for a long time: in the Neolithic period, stone axes made from Blue Elvan were exported from Cornwall to various parts of Britain.
- Turn right along the lane and follow it for roughly 0.3 miles/0.5 km until you reach a house on the left.
Even in Victorian times, slate was blasted with black powder (aka gunpowder), rather than high explosives such as dynamite. This is because high explosives combust with a supersonic shockwave known as a detonation wave, travelling at a speed of more than a mile per second. This causes very high pressure and resulting high temperature in the explosive, setting off neighbouring parts. This would shatter the brittle slate into tiny pieces, rather than breaking off large chunks.
As fuse technology improved, holes were drilled at regular intervals along a quarry face, filled with black powder. These pockets were all blasted simultaneously using a linked fuse (electrically triggered in the latter years of quarrying), to break off a very large chunk of slate. You can sometimes see the blasting holes in waste pieces of slate on the slate tips.
- Turn right through the gate opposite the house, into the field. Head straight across the field to the gate opposite.
- Go through the gate into the next field and follow the right hedge to another gate.
- Cross the stile next to the gate and head for the gate in the opposite (bottom left) corner.
- Cross the stile on the right of the gate and turn right onto the track above Fentafriddle. Follow the track downhill to the corner.
Fentafriddle is a group of farm buildings half-way up southern side of Trebarwith Valley. Fentafriddle was once a mill, fed by the spring and, later, powered by a donkey. In Cornish, Fenter means "spring" and friddle is thought to be a corruption of frosyel meaning "gushing". The settlement dates back to mediaeval times, mentioned in records of 1437. Until the early 20th Century, it was part of the estate of the Earl of Wharncliffe. Many of the farm buildings have been converted into luxury holiday accommodation, though the land around them is still farmed.
- Climb the wooden steps on your right and cross the stile, then follow the left hedge of the field to a stile at the bottom.
- Cross the stile and follow the path downhill, over another stile and down some steps onto the road to Trebarwith Stand.
- Turn left on the road and walk a short distance downhill to a public footpath sign on your right opposite the drive to Fentafriddle Farm.
The acidic soil in the Tintagel area was fertilised with lime-rich beach sand from nearby Trebarwith Strand, where the golden sand is largely composed of sea shells which are mostly calcium carbonate (chemically identical to chalk and limestone).
The sand at Trebarwith Strand was also put to another use: to avoid several tonnes of slate in a wagon going down the steep road through Trebarwith Valley resulting in horse paté, the slate wagons would be loaded with sand from Trebarwith Strand and this would be scattered on the road on the way back up, to act as a braking system.
The trade in sand and slate quarrying led to road improvements in the early 19th century and for one reason, or the other, or possibly both, the Trebarwith Strand to Condolden road is known as "Sanding Road".
- Opposite the driveway to Fentafriddle Farm, go through the gate to reach to a waymark at the bottom of the steps.
Roe deer live in the valley and you may encounter one, particularly if you are walking early in the morning.
The Roe Deer is unusual among hoofed animals as the egg is fertilised at the time of mating but then goes into suspended animation for several months - a process known as delayed implantation. This mechanism means that instead of being born in late winter, the young are born in early summer when food is more plentiful.
In most species with delayed implantation, the mother sends out a hormonal signal to tell the embryo to wake up. However in the case of the Roe Deer, the embryo has a built-in egg timer which sends a chemical message back to the mother that it's time to resume the pregnancy.
- Turn left at the waymark to cross the stile over the fence on the left and cross the stone bridge. Then follow the path indicated by white posts past a chalet, over a stile and to the top-right corner of the meadow.
- Climb the stone stile at the top-right corner of the meadow and follow the path up through the Trebarwith Nature Reserve to a stile into a field.
The Trebarwith Nature Reserve has a rich diversity of wildflowers and a thriving stream community in its unimproved meadowland. The area of Trebarwith Valley which is now the Nature Reserve was first used as agricultural land in the post-mediaeval period. It is likely that the path that runs through the reserve dates from this time, perhaps linking farmsteads to the parish church.
- Cross the stile into the field and walk parallel to the right hedge, until you see see a the wooden fenced area. The stile is in the right hand corner of the enclosure.
- Cross the stile onto the lane. Turn right on the lane and follow it to a T-junction in Trewarmett.
- Turn right at the junction and follow the road to the telephone box outside Park Farm.
Park Farm was derelict in the 1970s; when it was converted into holiday accommodation, the fields still contained many farming implements of the 19th century including horse-drawn ploughs and carts. Exactly how far the farm here dates back is unknown, though an axe-head from the Bronze Age was found amongst a pile of stones in the garden. The name is from the Cornish word Park which means "field".