Mortals who’ve never donned a wetsuit and crawled through muddy sumps have a chance to see one of the country’s subterranean jewels.

Craven Pothole Club is offering the chance to descend into the 340-foot chasm of Gaping Gill, in the shadow of Ingleborough, from next Saturday.

No caving experience is necessary: the descent is by winch and chair and you’ll be at the bottom of the main shaft in only one minute. The club floodlights the impressive main chamber for the event, so it’s worth taking a camera for some panchromatic mementos.

The winch operates from Saturday 19 August until bank holiday Monday, 28 August, from about 8am until 6pm, except on the final day, when you need to be there by 10am to ensure you get to your trip. Cost is £10 per person, including the re-ascent! Kids over the age of seven are allowed but must be accompanied by an adult.

You’ll need to walk in to Gaping Gill, so go equipped as for any normal hillwalking day. Shortest walk is from Clapham, though you could access the winch station from any route around Ingleborough. Just head for the big hole in the ground and the temporary tent city that springs up during these meets.

Winches down Gaping Gill operate only twice a year. Bradford Pothole Club puts on its service during late May bank holiday.

The main chamber is reputed to be big enough to swallow St Paul’s Cathedral and the descent includes a short guided tour. You can’t pre-book. Just turn up, but be prepared to queue at busy times. Fell Beck, which plunges into the cavern, is dammed during the meeting, but if it’s exceptionally wet weather, the service may be suspended. Ask in Clapham village before setting out on the walk if you’re in any doubt.

For details, check out the Craven Pothole Club website.