Clearwell Caves
The Rocks Coleford Royal Forest of Dean Gloucestershire GL16 8JR
The Forest of Dean is famous for its iron ore mines, and this is both a cave system and a mine, a natural set of caves but one where they have been digging out iron ore and ochre for centuries. Run these days by a father-and-son team, it's an impressive series of no less than nine caverns, and basic tours, which take around ninety minutes, take you 100 feet underground to see the best features of these, complete with mining equipment and other displays. If you're keen to experience a spot of proper caving they also lay on semi-deep and deep level tours for groups of at least eight, which take you up to 200 feet underground. Fascinating, but not for the faint-hearted.