Trewarmett Downs Short Walk
- Distance:1 mile
- Walk grade:Easy
- Start from:Trewarmett
- Recommended footwear:walking boots or wellies; trainers in summer
- Wildflowers in Spring and early Summer
- Panoramic views over Port Isaac Bay and Trebarwith Valley
- Turn left outside Park Farm and cross the road.
- Next to the post box in Trewarmett, take first turning on right between the old cottages (not the larger lane on the left to Trenale).
- A the top of this lane path leads up between two hedges through a tunnel of tree branches. Follow the path to the top where you reach a pedestrian gate on the right (about 10 mins walk)
- Go through the gate and explore the network of small fields. This was once common land so there is still a public right of way across it.
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).
The Prince of Wales quarry is in Trebarwith Valley, overlooking Trewarmett. The quarry opened in 1871 but was only worked for just over 20 years, closing 1890s; the slate quarried here was blue slate from the Upper Devonian Penpethy Beds. A circular path now leads through the old slate tips, past the quarry pit (now a lake with a small waterfall) and up to the engine house which has good views of the valley and coastline.
For more information see our page on Trewarmett Downs.