Titan is estimated to be about 459ft - 140m - from floor to ceiling, as high as the London Eye. Dave Nixon, a local potholer and leading underground explorer, discovered the cave after finding an account by an obscure 18th century academic in a university library.In a paper written in 1793, James Plumtree described a network of caves which went beyond Leviathan, a well-known cave system near Castleton. Mr Nixon and a group of Peak cavers realised the entrance must have been blocked by a rockfall, and, after removing rocks, they discovered a long system leading the group to Titan.
Cavers spent three years removing another fall of boulders before finally gaining entry to the bottom of the cavern. Mr Nixon said: "It wasn't a matter of stumbling, it was a lot of research and a lot of hard work."
His team has now completed a man-made shaft which allows cavers to abseil into the cave, saving them a challenging five-hour underground journey.
The cave was carved out over millions of years by water eroding limestone and contains a massive waterfall which plunges deep below ground level. Titan is nearly 197ft - 60m - higher than the previous record holder, Gaping Gyhll in the Yorkshire Dales.