Marble Arch Caves

18th–19th century: The Junction, Grand Gallery, and Pool Chamber The Marble Arch, Cladagh River resurgence and three large dolines on the plateau above the end of Cladagh Glen were all known well before underground exploration began; in fact the arch was a popular tourist attraction in the 19th century. 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. Without venturing far into the cave, Henry descended to the base of one of the dolines above the resurgence: The stream passages at the base of each shakehole were first explored by Édouard-Alfred Martel and Dublin naturalist Lyster Jameson in 1895. Using a canvas boat, and with candles and magnesium flares for light, Martel and Jameson found of passages, including the junction where the three rivers (the Owenbrean and the combined Aghinrawn and Sruh Croppa) meet. Bolstered by the experience, and the good possibility of further discoveries, the Yorkshire Ramblers returned in Easter 1908. A group of cavers descended a pothole located close to the large dolines on the plateau and discovered the Great Boulder Chamber. After a few hours of exploring, they realised that they had found a new route into Pool Chamber, bypassing the deep water of the original entrance. 1935–1938: Skreen Hill and connections No further exploration was made until Easter 1935 when another group from the Yorkshire Ramblers' Club made their way from England. In wet conditions, the cavers re-entered Pool Chamber via the entrance found in 1908, and after some investigation discovered a high-level crawling passage exiting the chamber. The passage ended high in the wall of New Chamber, a cavern of considerable size, where the upstream continuation of the river was found. Exploration was halted here as the water was too deep to pass. This section of deep water is where the path of the current show cave ends. During the 1935 expedition, another group of cavers explored Lower Cradle Hole Cave. On reaching the downstream end of the cave, they discovered that water levels were now low enough to see a series of low arches above the water surface. By anchoring a floating candle part-way through the passage, exiting the cave and returning to the end of the Grand Gallery in Marble Arch Cave, the cavers confirmed that the passages were connected; subsequently, two of the party swam through to make the first through-trip between Marble Arch Cave and Lower Cradle Hole Cave. The new section of river passage beyond was named Skreen Hill 2, and a further inlet passage was named Legnabrocky Way. A notable feature of the Legnabrocky Way is the Giant's Hall, a large chamber 60 m long, 30 m high and 15 m wide (200×98×49 ft). 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. William Frakes and John Ogden were the first to successfully pass the sump to reach Skreen Hill 3, of "magnificent stream passage" ending in boulder choke. The development also included boring a new entrance shaft into Skreen Hill and, significantly, excavating a corridor using quarrymens' plugs and feathers (instead of potentially damaging explosives) through the short section of rock separating Pool Chamber from New Chamber. This connected Skreen Hill all the way to The Junction for walking visitors for the first time. At this time, all known entrances to the cave system were gated to control access. From then on, cavers were only allowed access by agreement with show cave management. Those killed were Philip Marshall (20), Brian Patrick Kennedy (22) and Conleth Cormican (21). A memorial plaque outside Lower Cradle commemorates the disaster, and the entrance remains accessible to cavers via a gate. Three oak saplings were also planted on the grassy area south of the car park by each of the families on the tenth anniversary of the accident. 2009–2010: diving connections In 2009 and 2010, diving connections were made to nearby cave systems by Artur Kozłowski. Kozłowski made the first connecting dive to Prod's Pot – Cascades Rising, doubling the total length of the system from . extending the Marble Arch system to . The discoveries make this the longest cave in Northern Ireland. ==Hydrology and development==

The Marble Arch Cave system is chiefly formed from three rivers which drain off the Marlbank area on the north side of Cuilcagh mountain. From west to east, these tributaries are the Sruh Croppa, the Aghinrawn (or Monastir) and the Owenbrean. has a complex hydrology which includes drainage from at least five small sinks on the eastern Marlbank (Gortmaconnell Pot, Little Gortmaconnell Pot, Smokey Mountain Sink and two unnamed sinks at Brookfield have been dye traced to Cascades); sections of the Owenbrean River upstream of its main sink at Pollasumera; and most notably Goat Pot, Aghatirourke Pot, Pigeon Pots and Badger Pot on East Cuilcagh, nearly to the southeast. Of these, Goat Pot and Aghatirourke Pot have also been traced to Tullyhona Rising ( east-southeast from Cascades Rising); Pigeon Pots, Badger Pot and Aghatirourke Pot also flow to Gortalughany Rising (an overflow rising on East Cuilcagh); and Badger Pot and Pigeon Pots also flow to Shannon Pot on the far western slopes of Cuilcagh. == Show cave ==

Édouard-Alfred Martel first postulated that Marble Arch Cave would make a worthy show cave after initially exploring the system in 1895. Development included: • Building concrete and metal walkways with handrails throughout the show cave; • Installation of electric lighting; Between 1985 and 2008, the show cave attracted approximately 1 million visitors, from 100 countries worldwide. Annual visitor capacity (during the period that the cave is open, March–September) is 94,060. == European/Global Geopark status ==

In 2001, the caves and the nearby Cuilcagh Mountain Park joined to become a European Geopark under the name Marble Arch Caves European Geopark, the first park in the UK to be recognised by the European Geoparks Network (EGN). the park became part of the Global Network of National Geoparks (GGN) scheme and was renamed Marble Arch Caves Global Geopark. 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. == Conservation issues ==

The cutting of turf has led to damage in the area. Extensive drainage in parts of the bog has damaged the bog's ability to retain water, resulting in flooding and abnormally high water levels in the caves downstream. This has impeded tourist activity in the past, notably in 1989 when the impact of such damage influencing cave water levels first became evident. Another problem is that human interference can cause the limestone to be damaged or eroded. In a particular case in 1984, a group of vandals broke into the show cave before it was opened to the public and threw stones at some of the calcite formations around the entrance. Many small stalactites were snapped off at their bases, while the tip of the largest stalactite in the show cave (over in length) == Resources ==

See also • Cuilcagh Mountain Park • Cladagh Glen Nature Reserve • List of caves in the United Kingdom Notes References Cited sources and further reading • • External links • • Marble Arch Caves Earth Science Conservation Review. (National Museums Northern Ireland) • Map of the Marble Arch system (2010). Marble Arch Project. • Original video footage from connection between Marble Arch and Prod's Pot/Cascades systems (2010). Marble Arch Project.