Marble Arch Caves

[7] As early as the 1730s, the Reverend William Henry described these features, as well as the sinks of the Owenbrean, Aghinrawn and Sruh Croppa rivers which he correctly surmised to be feeders of the system.

[8] Without venturing far into the cave, Henry descended to the base of one of the dolines above the resurgence: The arch over my head was 20 feet high, continued with a little landing for 100 yards to the other great pit, by the light of which I could observe the river flowing gently along...

[9] Using a canvas boat, and with candles and magnesium flares for light, Martel and Jameson found 300 metres (1,000 ft) of passages,[10] including the junction where the three rivers (the Owenbrean and the combined Aghinrawn and Sruh Croppa) meet.

[NB 1][4] They drew a map of the discoveries and line drawings depicting the expedition, noting the upstream conclusion by boat in the Grand Gallery, and on foot at Pool Chamber.

[7] Martel and Jameson also investigated Cradle Hole, a very large surface shakehole 400 metres (1⁄4 mi) south-south-west of Marble Arch.

A group of cavers descended a pothole located close to the large dolines on the plateau and discovered the Great Boulder Chamber.

[7] When club members returned again in 1938 they brought an inflatable dinghy, allowing them to progress across the lake, only to discover that the way on was blocked by Sump 1, just 40 metres (132 ft) from the shore.

In December 1966 divers Dave Cobley and Mike Boon made preparations to dive Sump 1 in Skreen Hill passage.

Before making the dive however, they investigated a small dry passage leading off on the left bank of the lake, finding it to be blocked at the end by unstable boulders in the roof.

[18] The upstream continuation of the river in Skreen Hill 2 was found to be shortly blocked by Sump 3, so in March 1967 a team of divers returned to attempt further exploration.

From 1982 until after opening in 1985, sections of Marble Arch Cave underwent development to improve accessibility in order to accept tourist visitors.

As well as concrete pathways, safety barriers and electric lighting, this involved installing weirs and jetties for boat access to enable visitors to enter the caves by the same route that Martel and the early explorers took.

They were in a group of ten cavers, mostly students from University College Dublin and Dublin Institute of Technology caving clubs, when the three were swept away by fast running water and drowned in the low air-space (or "duck", (which was flooded to the roof on this particular occasion) section of passage between the end of Lower Cradle Hole and the Grand Gallery in Marble Arch Cave.

Kozłowski made the first connecting dive to Prod's Pot – Cascades Rising, doubling the total length of the system from 4.5 to 9 km (2.8 to 5.6 mi).

[2] The Marble Arch Cave system is chiefly formed from three rivers which drain off the Marlbank area on the north side of Cuilcagh mountain.

In 2008 the park boundaries were extended across the border into parts of County Cavan in the Republic of Ireland, making it the first international Geopark in the world.

It was then sent to the Ulster Museum in Belfast where a calcite resin was specially produced and subsequently used to stick the tip back onto its original position.

Black-and-white line drawing of an underground river, with a man standing in a boat, holding a flare which lights the arched ceiling.
Drawing by É. A. Martel, depicting the first exploration of Marble Arch Caves in 1895
A boat moored beside a concrete path on an underground lake, with darkness surrounding.
Today, visitors disembark at the same place that Jameson and Martel first made landfall.
Hand-drawn map of a cave, showing meandering underground river passage as well as surface topography including large shakeholes.
1908 survey of Marble Arch Caves by the Yorkshire Ramblers' Club
Cave passage with with dark water flowing towards the viewer beside a silty bank on the left. The cross-section of the passage is roughly triangular, with a flat, wide bottom, and a relatively smooth slanting roof on either side.
Lake in Skreen Hill at the upstream extent of the present show cave, shortly before Sump 1
Looking down into a wide, well-vegetated shakehole with steps leading down the right-hand-side, at the bottom of which a dark river is visible beyond a man-made concrete jetty.
One of the traditional entrances to the underground Cladagh River: now an entrance to the show cave by boat.
Downward tunnel with steps descending within, flanked by metal handrails. The tunnel is circular in cross-section and lined at the sides and above with corrugated steel.
The man-made show cave exit also serves as an entrance during times when boats are not in use.
Tourists looking in different directions, while standing on an elevated wooden walkway surrounded by darkness in a cave.
An elevated section of the walkway between New Chamber and Pool Chamber
A section of cave passage and walkway in the showcave
Cave passage with some features lit; within it a concrete pathway sinks to shoulder height with concrete walls either side. Dark brown water runs past outside and just below the top of the walls.
At the "Moses Walk", the path sinks into the riverbed to pass a low-ceilinged section of passage.
A long stalactite hangs from the ceiling of a cave passage, with some smaller calcite stalactites nearby.
A large stalactite, nicknamed "Martel's" by show cave staff, [ 35 ] was damaged by vandals before the attraction opened.