Bigger than the London Eye: UK's largest cave found

To the untutored eye, the mighty Peak Cavern looks as big as they get. Its entrance is the biggest in Britain and leads to vast geological miracles, including the serene Orchestra Gallery.

But local cavers always felt there was something bigger, buried beneath the hills of Castleton, Derbyshire. In a paper written in 1873, James Plumtree, an 18th-century academic, described a network of caves which went beyond Leviathan, a well-known system of underground holes near the town. When Plumtree's findings were discovered in a library at Cambridge University 14 years ago, they were republished and seized upon by those who enjoy burrowing around the Peak District's limestone cave systems.

It transpires that he was right. After a decade of painstaking graft through rubble, silt and water, a team of Derbyshire explorers has discovered the UK's biggest cave - Titan - a 140m-tall funnel-shaped shaft as high as the London Eye or the Humber Bridge.

The cavers' pursuit of the shaft started in 1996. The graft for caver Dave Nixon and his friends resembled that of coal miners. Crouching and stooping, they hacked through stones, silt and other obstacles with hand tools, propping up the roof with scaffolding as they went.

In 2002, the explorers hit what they called the "Titan Choke" - a vast vertical pile of boulders - through which they began an ascent. They hacked a route upwards, using explosives and scaffolding as they climbed. After six months they reached the top and peered up into the blackness of the Titan shaft. "Our feelings were a mixture of complete elation and excitement to tell everyone else," said Mr Nixon yesterday.

Using radio location equipment, Mr Nixon's team found Titan's location on the surface and dug a shaft from above for abseiling into the cave, saving a five-hour underground journey. This was captured in a BBC1 Inside Out documentary, broadcast in Yorkshire last night.