An underground Limestone quarry spanning over 35 Kilometers.

A remote sea cave on the Pembrokshire coast, home to some of the best cave formations in the UK.

A former underground coal mining museum.

A former underground ammunitions depot.

A former limestone quarry in Wiltshire.

A mixed-mine that had been worked for lead, barytes, and fluorspar, closing in 1998.

Former Lead mine dating back to 1869.

A small cave system residing near the popular Chrome Hill.

A 19th-century slate quarry, known for its extensive underground workings and rugged mountain setting.

An 18th century Bath stone mine

The largest underground stone quarry in the UK.

The last working mine in Derbyshire known for producing Fluorspar.

A Northern stone mine first worked in 1841.

A part natural, part mined cavern in Derbyshire. known for its impressive size and connecting systems.

Water Icicle Close Cavern in Derbyshire is a mix of natural cave passages and old mine workings, known for its formations and a deep entrance shaft.

This small Derbyshire mine, worked for lead and later fluorspar until 1987, was briefly used for a 1992 "Peak Practice" episode (leaving polystyrene boulders).

A small 19th-century lead mine in Derbyshire's Via Gellia.

A small cave system lying beneath the popular Chrome Hill in Buxton.

Part of the longest continually operated slate mine in the world until its closure in 2003.

Serving as a drainage channel for a popular Welsh quarry.