It’s a Sunday morning, and I’m feeling peaky. Not because of the larger-than-average Saturday night (although that’s probably not helping), but because I’m strapped into a tiny harness and gazing up a sheer vertical wall that’s supposedly only eight metres high. It looks like a kilometre to me.

My instructor, a chipper Scotsman named Gordon, is encouraging me to climb to the top, even though the only thing saving me from plummeting down again is a rope that’s attached to, er, Gordon. I take a deep breath and place my hands on the coloured grips. They seem fairly secure.

Before I know it I’m scrambling upwards, and suddenly I’m eight years old again, scaling the craggy rocks of my beach-side home town, fearless and full of adventure. I’m unleashing my inner monkey, trusting the power in my arms and legs, and converting adrenaline into determined concentration. That is, until I reach the top and look down… that’s definitely more than eight metres.

East London doesn’t have many actual mountains, so I’ve settled for an introductory session at the canal-side Mile End Climbing Wall Centre. It’s filled to the brim with beginners’ walls, outdoor bouldering and facilities for the pros. Skilled climbers dangle off clutches designed to strengthen the muscles in pinkie fingers, while others cling to the ceiling, defying gravity like spider-people. Meanwhile, tiny kids scramble around as parents chatter, apparently unperturbed, beneath them.

“Now you’re up there,” says Gordon, “the only guarantee is that you come down. You just have to do it well.” So I trust him, put all my weight in his hands and the harness, and abseil back down again. Safe and sound, I hit the ground, but I’m definitely still on a high.

Taster session £20, beginners’ courses £55. Haverfield Road, Mile End, E3 5BE  mileendwall.org.uk

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