Titan is a natural cavern

Cave

A cave or cavern is a natural underground space large enough for a human to enter. The term applies to natural cavities some part of which is in total darkness. The word cave also includes smaller spaces like rock shelters, sea caves, and grottos.Speleology is the science of exploration and study...

 near Castleton in the Derbyshire

Derbyshire

Derbyshire is a county in the East Midlands of England. A substantial portion of the Peak District National Park lies within Derbyshire. The northern part of Derbyshire overlaps with the Pennines, a famous chain of hills and mountains. The county contains within its boundary of approx...

 Peak District

Peak District

The Peak District is an upland area in central and northern England, lying mainly in northern Derbyshire, but also covering parts of Cheshire, Greater Manchester, Staffordshire, and South and West Yorkshire....

, and is the deepest shaft of any known cave in Britain

Great Britain

Great Britain or Britain is an island situated to the northwest of Continental Europe. It is the ninth largest island in the world, and the largest European island, as well as the largest of the British Isles...

, at 141.5 metres (464.2 ft). The existence of Titan was revealed in November 2006, following its discovery on 1 January 1999 after cavers discovered connections from the James Hall Over Engine Mine to both Speedwell Cavern

Speedwell Cavern

The Speedwell Cavern is one of the four show caves in Castleton, Derbyshire, England.It consists of a horizontal lead miners' adit leading to the cavern itself, a limestone cave...

 and Peak Cavern

Peak Cavern

The Peak Cavern, also known as the Devil's Arse , is one of the four show caves in Castleton, Derbyshire, England...

. Previously, the deepest known underground shaft in Britain had been Gaping Gill

Gaping Gill

Gaping Gill is a natural cave in North Yorkshire, England. It is one of the unmistakable landmarks on the southern slopes of Ingleborough – a deep pothole with the stream Fell Beck flowing into it...

 on the slopes of Ingleborough

Ingleborough

Ingleborough is the second highest mountain in the Yorkshire Dales. It is one of the Yorkshire Three Peaks, the other two being Whernside and Pen-y-ghent. Ingleborough is frequently climbed as part of the Yorkshire Three Peaks Challenge, which is a 24-mile circular challenge walk starting and...

 in the Yorkshire Dales

Yorkshire Dales

The Yorkshire Dales is the name given to an upland area in Northern England.The area lies within the historic county boundaries of Yorkshire, though it spans the ceremonial counties of North Yorkshire, West Yorkshire and Cumbria...

.

Dave Nixon, nicknamed Moose and guru of a group of Peak District cavers, discovered the shaft after finding an account by an 18th-century academic, James Plumptre

James Plumptre

-Life:James Plumptre was born at Cambridge on 2 October 1771, the third son of Robert Plumptre, President of Queens' College, Cambridge, by his wife, Anne Newcome. Anna Plumptre was his sister. James was educated at Dr. Henry Newcome's school at Hackney, where he took part in amateur theatricals....

, in a university library.