There I was, following Tom and Jeffro in those strange oversized orange suits. The sun was setting to the left below us, the grassy hill of the peak district loomed higher to our right. We followed a winding route along the expanse of muddy slope, relying on Tom’s mysterious ability to locate caves, like a Terrier finds a buried bone.

A single well was lying tucked into fold in the hill, ancient and asleep. We removed the metal grating, and I shone my torch down. It saw no more than a few meters, until the rock narrowed. Oh right, I thought. We are just practicing SRT down a well.

I lowered myself down the well, and reached the narrowing. The smooth rock walls curved, and releasing my braking descender in jolts, I followed the curve of the walls like I was on a giant slide.

‘Good morning’, Jeffro offered, as I landed in a hall piled with boulders. The brown walls of rock were far apart, and the ceiling was high.

We scrambled steeply downwards, following a gentle stream, the walls and ceiling slowly drawing together, until they formed a small window of blackness. I crouched with Tom, peering into the darkness. The rope that Jeffro had descended down was still moving; a sign that life can exist on the other side.

‘Rope free’, I heard from far away. And I was next. Attaching my cowstails to the bolt, I stepped though the window. The sound of crashing water echoed around me. I was in a shaft of rock that seemed to extend above me and below me for infinity. The confusing S-shape seemed to tie itself to my descender, because the next moment I was abseiling over the edge. The wall vanished in front of me and I swung inwards. A torrent of icy water poured down on me. I abseiled down to the bottom. Nobody was there.

A light shone through the sheet of falling water. Ducking under the waterfall, I found myself in a space of smooth rock, warm and out of the spraying water. This was our lounge to enjoy; a space behind a waterfall, through an ominous black window, at the bottom of a well.