Hidden beneath the surface of the UK is a subterranean world of mysterious caves and incredible caverns. Here are ten of the best.
1. Alum Pot, Yorkshire
A lost world that few people get to see, Alum Pot is an 80m open shaft. To reach it, caving experts Lost Earth Adventures can take you on a journey through the underground stream of Long Churns and down the Dolly Tubs descent. In the sunlit cavern itself, you can abseil and traverse across the centre to ‘The Bridge’.
Level: Suitable for beginners.
Try it: A full day of caving with Lost Earth Adventures in Alum Pot starts from £85 per person.
2. Gaping Gill, Yorkshire
One of the UK’s longest cave systems, Gaping Gill’s enormous main chamber is 129m long and 31m high. The first descent was made in 1865 by Edouard Martel, who used a telephone to speak to the surface team. Today, you can make the same descent using a winch that’s managed by the Bradford and Craven pothole clubs. You can only access the system twice a year so get it booked in the diary.
Level: Suitable for beginners.
Try it: Visit Bradford Pothole Club (operate over the May bank holiday) or Craven Pothole Club (operate over the August bank holiday) for dates and details on where to meet. A trip down will only set you back £15.
3. The Easegill system, Yorkshire
Britain’s largest cave system straddles three counties and has more than 40 miles of passageways. With several entrances, one of the most popular is the 33m drop at Lancaster Hole. Nearby is a series of floor to ceiling columns – in the 1960s, one column was climbed, broken and repaired with glue. Access to most areas is by permit only, so you’ll need to plan ahead. For details, see Red Rose Cave and Pothole Club site.
Level: Best for experienced cavers
Guided trips: Around £50pp with Yorkshire Dales Guides, they also offer summer caving introduction trips from £15 per person.
4. Ogof Ffynnon Ddu, South Wales
At 300m deep, the ‘Cave of the Black Spring’ is Britain’s deepest and third longest cave. Navigation is notoriously tough, with 30-miles of windy passages, waterfalls and potholes. Some sections are submerged in water, so you’ll be holding your breath in parts.
Level: Best for experienced cavers and clubs.
Try it: A Site of Special Scientific Interest, access is restricted to bona-fide caving clubs who can contact the OFD Cave Management Committee for access arrangements. You can also contact South Wales Caving who own one of the entrances. Paid-for caving is not permitted.
5. Ogof Draenen, South Wales
‘Hawthorn Cave’ has more than 40-miles of passageways, making it the longest cave system in Wales. This vast complex features fantastic mineral deposits that decorate huge caverns like the ‘War of the Worlds’.
Level: Experienced cavers that belong to caving clubs.
Try it: The road by the Pwll Du Adventure Centre leads to the only permitted entrance. No profitable activities are permitted, so exploration is restricted to caving clubs. Visit the Pwll Du Cave Management Group website for more info, and contact the Access Secretary (Sue Mabbett) for the key.
6. Porth yr Ogof, South Wales
Set in the southern Brecon Beacons, Porth yr Ogof has the largest cave entrance in Wales, at more than 17m wide and 5m tall. With lots of route options for all abilities, first-timers can follow a guide through the easiest sections, while experienced cavers have tight crawls, sumps and a maze of passageways to tackle.
Level: All abilities, including kids.
Try it: It will cost £55 per person in a group (6 or more) with Adventure Britain.
7. Clearwell Caves, Gloucestershire
One for families and first timers, this natural cave system has been mined for iron ore and ochre pigment for thousands of years. All abilities can join a deep-level cave tour, descending 60-metres underground to crawl, walk and scramble through the passageways.
Level: All levels, including beginners and kids.
Try it: Find out more on the Clear Well Caves website. A guide will cost £25 (adult deep level caving) or £15 (adult semi-deep level).
8. Swildon's Hole, Somerset
Beneath the Mendip Hills lies Britain’s largest underground river system and a huge network of caves. In 1934, the UK’s first cave diving attempt took place here at Swildon's Hole. All abilities can explore this cave, with novices starting in the upper passages before progressing to the climbs, squeezes and sumps (underwater sections) in the main stream.
Level: All abilities, including beginners.
Try it: For guided trips, hit up Adventure Caving. It will cost between £45 and £92.50 (depending on group size).
9. Giant’s Hole, Peak District
Narrow passages, thirty-feet drops, rushing waterfalls and weird rock formations: welcome to Giant’s Hole. A stream flows into the entrance and leads to a series of sumps. Some parts are suitable for novices but the best bits lie beyond Garland’s Pot – a 7m descent that leads to complex passages and technical caving.
Level: All abilities, including beginners (with a guide).
Try it: It will cost around £89 per person for a caving course with Dolomite Training (prices are lower for larger groups).
10. Fingal's Cave, Inner Hebrides
A sea cave set on the uninhabited Scottish island of Staffa, Fingal’s is formed entirely of hexagonally jointed basalt columns. Inside, the arched roof creates cathedral-like acoustics. You can explore via a walkway that leads above high water level. Sir Walter Scott called it “…one of the most extraordinary places I ever beheld.”
Level: All abilities.
Try it: Book a boat trip with Staffa Tours. Prices start from £30 for a three hour boat trip (with one hour in the cave).