Prince of Wales Quarry Circular Walk
- Distance:0.5 mile
- Walk grade:Easy
- Start from:Prince of Wales quarry car park
- Recommended footwear:Walking shoes or trainers
- Engine House
- Slate tips covered in wildflowers in Spring and early Summer
- Wildlife such as buzzards and kestrels
- Elderflowers in early Summer
- Blackberries in late summer and early autumn
- Sloes and Elderberries in Autumn and early winter
- From the parking area, head uphill, through a gate, to a fork in the path.
Just the other side of the gate are a number of blackthorn trees, so if you want to make sloe gin this is a good place for picking in autumn. See the page on foraging for sloes for a recipe which can also produce sloe sherry and sloe cider too.
- Where the path forks, take the left path (more or less straight ahead) which climbs through the slate tips then levels out. Follow this until, just before the path ends, you reach a a few slate steps on your right leading up onto a wall.
The path ends in a platform which overlooks a waterfall, tumbling into the quarry pit. This is the stream that runs across Trewarmett Downs. When the quarry was being worked, the engine house pumped the water out of the pit, to prevent it flooding, and also powered slate-hauling equipment to lift the slate out of the pit.
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.
- Take the steps and follow the path up the side of the slate tip to the top, where there is a good view over the quarry pit.
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.
- At the top of the steps, turn left along the wall and follow the path down to the engine house door.
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).
- Facing out from the engine house doorway, take the path to the left and descend a series of steps. When you reach the bottom, turn left to reach the gate through which you entered.
For more information see the following page on the Prince of Wales Quarry.