Owen, 12, was thrilled when I booked a coasteering adventure with Cumulus Outdoors, a company specialising in outdoor adventures and residential programmes. We’d hoped to go coasteering in West Wales but Storm Ellen sank that plan. We arrived at the Cumulus base in Langton Matravers, just outside Swanage, with a sense of excitement – and, for me, a few butterflies.

Our guides were welcoming and patient, which was good as we took time to get into our wetsuits. (Karen, as a former guide leader, would have hurried us up.) We began the trek to the starting point, the stunning Dancing Ledge on Dorset’s Jurassic coast, England’s only natural world heritage site.

We were soon walking into the sea to acclimatise ahead of our first jump. The excellent guides gave us the most important advice: to tap our helmets and give a thumbs up after each jump, to confirm all was well.

We were amazingly lucky with the weather. The English Channel looked like the Mediterranean under a perfect blue sky. How ironic that a company named after a cloud could have given us a cloudless sky! I could have stayed in the water all day, with the sun on my face and a smile in my heart.

I knew jumping into the sea would be fun. I didn’t realise that Cumulus would take us into the wonderful sea caves as well. The photo above shows Owen traversing one of the narrower ones. The guides helped and reassured us every step of the way.

I was so glad I took my GoPro. After all, why have an action camera if you don’t take it on adventures like coasteering? The stills from the video made me smile with happiness remembering a magical few hours. I was impressed that the lens remained clear the whole time. (I was less impressed by the way the camera wouldn’t respond to the controls. I remembered my old trick of taking the battery out and putting it back in – a bit risky when perched on a slippery sea ledge!)

Dorset is a beautiful county. It may not have the stark wonder of Cornwall, but the combination of the extraordinary Jurassic coast, rolling hills and soft-focus villages make it irresistible.

The Cumulus coasteering sessions start from Langton Matravers. The imposing building next-door used to be Durnford School, a notoriously spartan establishment that ordered the boys to ‘strip and swim’ from Dancing Ledge. After a boy drowned, the headmaster Thomas Pellatt ordered local quarrymen to blast a swimming pool out of the rock on the ledge. Ian Fleming, the creator of James Bond, attended the school.

You can see the pool on the ledge today. A few people were enjoying the warm water when we prepared to enter the sea.

Cumulus, like countless other businesses, has been hit by the coronavirus lockdown. It resumed activities in early July after England relaxed lockdown. But schools may not be booking outdoor activities with companies like Cumulus, depriving them of valuable income. If you get the chance, do book coasteering and other adventures. You will love it, and Cumulus and other providers will benefit from the business. We want them to be there for us once the pandemic is over.