Speedwell Cavern is one of the four

show cave A show cave—also called tourist cave, public cave, and, in the United States, commercial cave—is a cave which has been made accessible to the public for guided visits. Definition A show cave is a cave that has been made accessible to ...

s in Castleton,

Derbyshire Derbyshire ( ) is a ceremonial county in the East Midlands, England. It includes much of the Peak District National Park, the southern end of the Pennine range of hills and part of the National Forest. It borders Greater Manchester to the nor ...

England England is a country that is part of the United Kingdom. It shares land borders with Wales to its west and Scotland to its north. The Irish Sea lies northwest and the Celtic Sea to the southwest. It is separated from continental Europe b ...

. The cave system consists of a horizontal lead miners' adit (a level passageway driven horizontally into the hillside) 200 metres below ground leading to the cavern itself, a

limestone Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...

cave. The narrow adit is permanently flooded, so after descending a long staircase, access to the cave is made by boat. At the end of the adit, the cavern opens up with

fluorspar Fluorite (also called fluorspar) is the mineral form of calcium fluoride, CaF2. It belongs to the halide minerals. It crystallizes in isometric cubic habit, although octahedral and more complex isometric forms are not uncommon. The Mohs scal ...

veins,

stalactite A stalactite (, ; from the Greek 'stalaktos' ('dripping') via ''stalassein'' ('to drip') is a mineral formation that hangs from the ceiling of caves, hot springs, or man-made structures such as bridges and mines. Any material that is soluble an ...

s and

stalagmite A stalagmite (, ; from the Greek , from , "dropping, trickling") is a type of rock formation that rises from the floor of a cave due to the accumulation of material deposited on the floor from ceiling drippings. Stalagmites are typically ...

s, and the so-called "Bottomless Pit". This chamber has an underground lake with a high waterfall and an extremely deep vertical shaft, now choked to within of the surface by rock spoil dumped by miners. The original depth of the shaft has been estimated, from the amount of spoil placed in the shaft over the years, at around . The mine was developed in the 1770s but the limited lead ore deposits meant that it was not profitable and it was closed down by 1790. At the foot of

Winnats Pass Winnats Pass (or Winnats, as shown on some Ordnance Survey maps) is a hill pass and limestone gorge in the Peak District of Derbyshire, England. The name is a corruption of 'wind gates' due to the swirling winds through the pass. It lies west of t ...

, it is a tourist attraction with an underground boat trip to the cavern. Originally the guide propelled the boat by pushing against the walls with his hands, later the boat was legged through, and now it is powered by an electric motor. A connection was discovered in 2006 between the Speedwell Cavern system and

Titan Titan most often refers to: * Titan (moon), the largest moon of Saturn * Titans, a race of deities in Greek mythology Titan or Titans may also refer to: Arts and entertainment Fictional entities Fictional locations * Titan in fiction, fictiona ...

, the largest natural shaft in the UK, which is high.

References

{{Derbyshire Places of interest Caves of Derbyshire Tourist attractions in Derbyshire Tourist attractions of the Peak District Show caves in the United Kingdom Limestone caves