Larger than any dog, let alone a house cat, the beast swaggered through the Dartmoor mist. My schoolfriends and I were entranced – until the adults who had slept through everything told us we were lying

I was 11, with a handful of friends on a school trip to Dartmoor. We’d set up our tents near the edge of a camp, which was mostly empty.

The first morning, our tent woke before the teachers. We stole out to find another group of boys already on the dewy grass, standing hands in pockets, together in nature. The sun was just coming up. The last of the night-time mist was peeling away.

We were making jokes in the way boys that age do when trying to stay silent – pulling exaggerated faces, making rude gestures – when someone pointed. There in the distance, perhaps 15 metres (50ft) away, stalking just beyond the wire fence, was a dark shape in the fog. It moved closer, from right to left across our field of vision – the unmistakable shape of a big cat. Much, much bigger than a house cat, more the size of a large dog. Bigger, even.

There is a distinctive, swaggering weight to the movement of a cat that size. The shoulders roll. The head is squarer, the tail longer and thicker than a house cat’s, with a distinctive slope. We stood there, transfixed, in total silence. I can remember its dark fur silhouetted against the thin white mist behind. The animal didn’t seem in a rush to leave. We were so shocked that we didn’t know how to feel. Half scared, half in disbelief. Fascinated. None of us had heard of anything like this before.