The Caves of the Tullybrack and Belmore hills are a collection of caves in southwest County Fermanagh, Northern Ireland. The region is also described as the West Fermanagh Scarplands by environmental agencies and shares many similar karst features with the nearby Marble Arch Caves Global Geopark.
The caves are situated under the hills of Tullybrack (386 m (1,266 ft)) – which incorporates Glenkeel (373 m (1,224 ft)) and Knockmore (280 m (920 ft)) – and Belmore (398 m (1,306 ft)), and feature three major cave systems: Reyfad–Glenkeel, Noon's Hole–Arch Cave and Boho Caves. [1] [2] They have been described as nationally significant by the Northern Ireland Environment Agency. [3]
The caves and related features are formed predominantly in the Dartry Limestone Formation – a sequence of rocks assigned to the Asbian sub-stage of the Visean stage of the Carboniferous period. Within this formation, the Knockmore Limestone Member is also an important cave-forming rock sequence. Cave development occurred within the Quaternary period and certain features are ascribed to the Holocene epoch of the last 10,000 years.
With the exception of Arch Cave, all of the caves and related karstic features listed below have been designated as provisional Areas of Special Scientific Interest (provisional ASSIs, or PASSIs), a conservation designation in Northern Ireland equivalent to SSSIs in other parts of the United Kingdom.
Grid Ref: H12684431. The Boho Caves are a selection of caves encompassing the main Boho Cave, the smaller Waterfall Cave and Upper and Lower Ravine Caves. The Boho Cave system is the sixth-longest cave system in Northern Ireland [4] and is the only example of joint-controlled caves in Northern Ireland. [5]
Grid ref: H108436. This small cave is part of the Boho Cave system and has been designated a Provisional Area of Special Scientific Interest (PASSI) site. The substrata dates from the Holocene epoch of the Quaternary period and is composed of limestone. There are two passages in this cave estimated to be about 8 m (26 ft) long, one of which has been enlarged as a souterrain and is also a scheduled ancient monument. [6] [7]
Grid ref: H10884343. This cave is also part of the Boho Cave system and has been designated a PASSI. The substrata date from the Holocene and are composed of limestone. This formation can be crawled through in dry conditions. [7] [8]
Grid ref: H12214311. (Irish : Poll na gColm, meaning "hole of the doves"). This site is designated as a PASSI. The rocks comprise Dartry Limestone, chert, and some calcite formations. The cave can be entered by a previously collapsed roof structure through which a large waterfall flows. The stream runs through the cave until it comes to a boulder choke which has so far proved to be impenetrable. The stream resurfaces onto the valley floor of the Aghanaglack River 1.8 km to the west north west. [9]
Early speleological visits to the cave include that of Henry Lyster Jameson in 1895, primarily to collect specimens of fauna. [10]
The second karst system in the Boho area is known as the Reyfad–Carrickbeg system, containing a number of very impressive features. The Northern Ireland Environmental Agency describe this system as follows: "the quality of geomorphological and geological features in the Reyfad–Pollnacrom–Polltullybrack cave system make it arguably the most important underground karst site in Northern Ireland." [3]
Grid ref: H11724670. The rocks here date from the Quaternary, Carboniferous period and are designated PASSI. This cave is approximately 1 km long in a north–south direction and is divided into two parts. The main body of water flowing through the cave is traversable, but there is a 10 m flooded sump which emerges in another section known as the Farr Out Series. [11]
Carrickbeg Rising is the proven resurgence of four major stream sinks within the system: Pollnacrom, Polltullybrack, Waterfall Sink and Watson's Sink. [12]
Grid ref: H09254750. The passages here date from the Holocene. The area has been designated a PASSI. Fairy Cave has been speculated to be part of a previous series of passages of the main Reyfad system. There is a small passage that runs along the joints of the bedrock and is only 1 m in height, which terminates in a sump; beyond this is a silt-choked hole. [13]
Grid ref: H10694635. The rocks of this sinkhole are of Knockmore Limestone. The hole is designated a PASSI and is one of a pair of dolines. A small stream flows into the sinkhole, which is estimated to be 10 m deep. It has been determined that the water from this hole emerges at Carrickbeg Rising. [14]
Grid ref: H096465. The rocks of this sinkhole consist of Dartry Limestone, Knockmore Limestone and chert. The site has been designated a PASSI. Little Reyfad is at the base of a shakehole. A series of descents (7 m) leads to a floor of broken chert, followed by a further 3 metre difficult descent to another base, which is blocked with a rock and gravel. [15]
Grid ref: H09444666. The rocks of this sinkhole are composed of Dartry Limestone and Knockmore Limestone with inclusions of chert. The sinkhole originates in peat and then cuts into limestone rock. There are a series of chert base levels which have been broken up to give access to further passages. When the substrata changes into Knockmore Limestone, the character of the cave changes to a more vertically oriented passage. After some more climbing there is a 22 m vertical drop with a further crawl at the base, which leads to a completely flooded section or sump, which itself is completely blocked up with silt. Above this is a very high roofed chamber or aven. [16]
Grid ref: H10054613. The rocks of this formation date from the Quaternary (Holocene) period and consist of limestone. The area is designated a PASSI.
Murphy's Hole is situated at the north end of a depression that also contains Seltanacool Sinks. A waterfall drains into the sink, which takes a large volume of water in heavy rains. Water draining here has been dye traced to the resurgence at Carrickbeg. [17]
Grid ref: H100470. The substrata from this formation dates from the Quaternary (Holocene) era and is composed of limestone. Designated a PASSI, it is situated in a cliff of Knockmore Limestone.
This cave is linked to a series of springs. The longest passage here is reported to be no more than 15 m (49 ft). [18]
Grid ref: H11744557. The rocks from this sinkhole are of Carn and Dartry Limestones. The site is designated a PASSI. This hole floods in wet weather. [12] [19]
Grid ref: H11834513. Also known as Pollkerran, [20] this sinkhole is designated a PASSI. The strata consist of Carn Limestone with mudstone and shale deposits. This formation is thought to have been a cave roof, which has collapsed, normally known as a shakehole. The debris from the collapse has formed what is known as a 'choke hole'. Investigations have determined that the stream which sinks into Pollkeeran rises again 2 km to the north at Carrickbeg Rising Cave.
Extreme caution is advised as this sink is extremely dangerous and attempts to explore should only be undertaken by very experienced cavers. [20] [21]
Grid ref: H11654582. The rocks from this shakehole are of Carn Limestone. The shakehole contains two sinks and is surrounded by cliffs on three sides. In wet weather, the sinks flood and water up to 2 m deep can build up. It has been ascertained that the water from Pollmore emerges at Carrickbeg Rising. [22]
Grid ref: H08534702. The rocks from this formation are composed of Dartry and Knockmore Limestones with chert and gypsum. This site has been designated a PASSI.
This cave is part of the main Reyfad system that links to the 'Heaven and Hell' passage. It has a small, wet entrance. The cave contains two shafts at 50 and 15 m respectively, which permit entry to the main stream passage which trends in a north-west direction for 100 m (330 ft) before turning south. The cave has been explored for 600 m (2,000 ft) to an impassable sump. An attempt to force through this route in 1981 led to the death of a diver. [23] [24]
Access is by permission of landowner only. [25]
Grid ref: H09214672. (Irish : Poll Tulaigh Breac, meaning "hole of the speckled hillside"). The rocks in this second major entrance to the Reyfad system are composed of Dartry and Knockmore Limestones with chert and calcite formations. This cave is designated a PASSI.
There is a very tight entrance to this cave through a sinkhole in what is known as a dry valley, but this eventually expands into a wider cave. The continuation of the passage contains many boulders and a deep pool, followed by 250 m of difficult passage which ends in a submerged section, through which cavers have to duck. A short distance beyond this there is a 53-metre shaft, which is the longest-known pitch of any Irish cave. The cave joins up with the Reyfad system just north of the main chamber. Just before this are chambers known as the 'Grottoes', which contain fine examples of calcite features including stalactites, helictites and cave curtains. [26]
Access is by permission of landowner only. [25]
Grid ref: H10234633. The rocks from this pothole are limestone with some gravel. The site, located in moorland, has been designated a PASSI.
Rattle Hole consists of a single shaft of 36 m (118 ft) depth, which terminates in a boulder strewn base. This provides access to a second chamber, which is a further 25 m (82 ft) deep and ends in a gravel base. Further efforts at extending this passage have proved fruitless, but as a result of dye testing it is known that the water from here emerges at Carrickbeg. [27]
Grid ref: H08894687. The rocks from this formation comprise Carn and Dartry Limestones with some Glenade Sandstone. Breccia, chert, calcite and gypsum deposits can also be found. [28]
This cave is noted by the Northern Ireland Environment Agency as being the most important underground karst site in Northern Ireland. [3] At 193 metres (633 ft) deep and 6.7 kilometres (4.2 mi) long, it is the deepest cave system in Ireland [29] and the second-longest in Northern Ireland. [4] This site is a PASSI and is a very active cave with many calcite formations and fossiliferous limestone, which includes evidence of Brachiopods and Crinoids. The extended area is hypothesised to have formed from the last glacial period (Pleistocene). [28] [30] [31]
Access is by permission of landowner only. [25]
Grid ref: H102458. (Irish : Séilteán a Cúil, meaning "rear rocky range"). The rocks from this line of three sinks date from the Quaternary (Holocene) and consist of limestone. It is thought that the sinks, which are situated in the same depression as Murphy's Hole, [17] link to Carrickbeg Rising. [32]
Grid ref: H1037 4790. This cave is also known as Ooghboraghan. The rocks comprise Dartry Limestone, Glenade Sandstone, Glencar Limestone, Knockmore Limestone, Meenymore Formation. These are found together with breccia, chert, limestone, mudstone and calcite. [33]
Grid ref: H09344765. Also known as Pollaphylla or Pollasod, the rocks of this pothole comprise Dartry and Knockmore Limestones. The site is designated a PASSI.
This sinkhole contains a substantial shaft of 30 m (98 ft) depth, with some crawling sections and short passages which ultimately end at an impenetrable crack in the rocks. The stream passing through Aughakeeran is believed to join the drainage through Pollanaffrin. [34]
Grid ref: H09374793. The rocks from this sinkhole comprise Dartry and Knockmore Limestones. The formation is designated a PASSI. The water flowing into this sink is thought to emerge into 'High Noon's' in the Noon's–Arch system. [35]
Grid ref: H09954771. [36]
Grid ref H08845047. Situated 50 m from Knockmore summit, this is a small cave of mainly archaeological significance, and is partially man-made. [37] The rocks in which it is formed is Knockmore Limestone. [38]
The cave is named for the art and writing of varying age inscribed on the walls. It was investigated by William Wakeman (1866–70) [39] [40] [41] and Thomas Plunkett (1878 and 1898) [42] and is now a scheduled ancient monument. The cave, described in the paper by Wakeman in 1868 as lying 'in the midst of a desolate, heath-clad highland, which extends over a considerable portion of northern Fermanagh, with no trace of cultivation, ancient or modern" . [39] He also describes it as situated beside a lake four miles and a quarter to the west and north of the police station of Bohoe (Boho). [39]
Grid ref H09244844. The rocks from this formation comprise Dartry Limestone and Knockmore Limestone. The feature is designated as a PASSI.
This sink is found in a forested area containing a small stream, which sinks in several places. The water from the stream is believed to enter 'Inlet 1' beside 'Artie's Chamber' in the Noon's–Arch system. [43]
Grid ref: H09354754. The rocks from this sinkhole comprise Dartry Limestone and Knockmore Limestone. The area is designated a PASSI.
A large river enters this pot hole when there is much rain. The cave follows many twists and drops and is of considerable length before it terminates at an impasse. It has been speculated that the water from this system enters Noon's Hole. [44]
Grid ref: H08964860. This sink forms part of the Noon's Hole–Arch Cave complex and the rock in which it is formed comprises Dartry Limestone and Knockmore Limestone. The site, which is designated a PASSI, features a narrow bedding plane leading for 12 m to a waterfall and a duck. It has been speculated that the water from this sink also joins the Noon's Hole drainage system. [45]
Karst is a topography formed from the dissolution of soluble rocks such as limestone, dolomite, and gypsum. It is characterized by underground drainage systems with sinkholes and caves. It has also been documented for more weathering-resistant rocks, such as quartzite, given the right conditions. Subterranean drainage may limit surface water, with few to no rivers or lakes. However, in regions where the dissolved bedrock is covered or confined by one or more superimposed non-soluble rock strata, distinctive karst features may occur only at subsurface levels and can be totally missing above ground.
Belmore Mountain is a hill in the townland of Gortgall, western County Fermanagh, Northern Ireland. With a summit roughly 398 metres (1,306 ft) above sea level, it is the second highest point in Fermanagh, the highest being at Cuilcagh on the Northern Ireland–Republic of Ireland border in the south of the county. The historian John O Donovan (1834) states that the indigenous population called the mountain Bel Mor Muintir Pheodachain.
Boho is a hamlet and a civil parish 11 kilometres (7 mi) covering approximately 12 km × 7 km southwest of Enniskillen in County Fermanagh, Northern Ireland. It is situated within Fermanagh and Omagh district.
The Marble Arch Caves are a series of natural limestone caves located near the village of Florencecourt in County Fermanagh, Northern Ireland. The caves are named after the nearby Marble Arch, a natural limestone arch at the upstream end of Cladagh Glen under which the Cladagh River flows. The caves are formed from three rivers draining off the northern slopes of Cuilcagh mountain, which combine underground to form the Cladagh. On the surface, the river emerges from the largest karst resurgence in Ireland, and one of the largest in the United Kingdom. At 11.5 kilometres (7.1 mi) the Marble Arch Caves form the longest known cave system in Northern Ireland, and the karst is considered to be among the finest in the British Isles.
Hanging Rock is a large limestone cliff with an obtuse angle. It is located beside the village of Florencecourt in County Fermanagh, Northern Ireland, and is part of the Cuilcagh mountain region. The cliff is situated in an area dedicated The Hanging Rock Nature Reserve, which is in turn part of the Marble Arch Caves Global Geopark.
The Cladagh River is a small river in County Fermanagh, formed from three rivers and a number of streams draining off the northern slopes of Cuilcagh mountain, which combine underground in the Marble Arch Cave system. On the surface, the River Cladagh emerges from one of the largest karst resurgences in the UK, before flowing through Cladagh Glen Nature Reserve and eventually draining into the Arney River.
Noon's Hole lies about 5 km northwest of the centre of Boho, in the townland of Old Barr in the parish of Devenish, County Fermanagh, close to the border with Boho parish. The cave is under part of the escarpment on the east side of the Glenade Sandstone uplands. At 81 m (266 ft), this pothole was thought to have the deepest shaft in Ireland, but this honour was passed to the nearby Reyfad Pot, which contains an entrance shaft of 88 m (289 ft). The continuation of the cave system contains 3.7 km (2.3 mi) of passage, and it connects to the resurgence at Arch Cave through three cave dives, making this system the 8th deepest in Ireland, at 108 m (354 ft).
The Sillees River is located in south-western County Fermanagh. Its origins lie in Lough Ahork, which is located in Lough Navar Forest. From here it continues through Correl Glen, Derrygonnelly and the Boho countryside, passing through both Carran and Ross Loughs where it ends in Lower Lough Erne.
The Boho Caves are a collection of caves centred on the village of Boho, County Fermanagh on the northern slopes of Belmore Mountain. They encompass the main Boho Cave and the smaller Waterfall Cave and Upper and Lower Ravine Caves. The Boho Cave system is the sixth-longest cave system in Northern Ireland, is designated an Area of Special Scientific Interest and is the only example of joint-controlled caves in Northern Ireland.
Knockmore is an upland area and townland situated in County Fermanagh, Northern Ireland outside the village of Derrygonnelly, in the historical barony of Magheraboy. This area, together with the adjacent Barrs of Boho and most of the uplands in Boho parish, are described as the Knockmore Scarplands. The focal point of the area is Knockmore summit at 277 metres (909 ft).
Killydrum is a townland in County Fermanagh, Northern Ireland. It has previously been referred to as Kildrome (1659) and Killdrum (1695). This townland belongs to the land division of Old Barr in the area of Boho.
Reyfad is a townland in County Fermanagh, Northern Ireland. It lies in the land division of Old Barr, in the civil parish of Boho. The townland has previously been called Rayfadd - 1659, Raffada (Magheryboy) - 1672 and Ráith Fada "long fort" - 1833.
Aghanaglack or Aghnaglack, is a townland in County Fermanagh, Northern Ireland. It is situated in the civil parish of Boho, as well as Fermanagh and Omagh district.
The Marble Arch Caves Global Geopark straddles the border between Northern Ireland and the Republic of Ireland. It is centred on the Marble Arch Caves and in 2001 it became one of the first geoparks to be designated in Europe.
The Cliffs of Magho are a 9-kilometre-long (5.6 mi) limestone escarpment located in the townland of Magho, County Fermanagh, Northern Ireland. The NNW-facing cliffs overlook the western reaches of Lower Lough Erne and define the northern edge of Lough Navar Forest, a major plantation managed by the Forest Service of Northern Ireland. A popular viewpoint atop the cliffs is accessed by a forest drive.
Drumbegger is a townland situated in County Fermanagh, Fermanagh and Omagh district, Northern Ireland. It is part of the civil parish of Boho in the old barony of Magheraboy and contains the sub-townland known as Oubarraghan.
Agharahan is a townland is situated in the land division of Old Barr in the parish of Devenish, Barony of Magheraboy. It has an area of 746,831 m² / 74.68 hectares /0.29 square miles/184.55 acres / 184 acres. The townland runs from the high plateau in the Knockmore Scarpland at 766 ft down to the lowlands at 177 ft above sea level and is between the townlands of Old-Barr to the west, Killydrum to the south, Aghakeeran to the north, Drumbegger to the east and Lattonagh to the south. Agharahan is in the Civil Parish of Devenish but was previously associated with the civil parish of Boho, County Fermanagh.
The Tyrone Group is a lithostratigraphical term coined to refer to a particular succession of rock strata which occur in Northern Ireland within the Visean Stage of the Carboniferous Period. It comprises a series of limestones, shales and sandstones which accumulated to a thickness of 2400m in the northwest Carboniferous basin of Ireland. The type areas for the group are the Clogher Valley of County Tyrone and the Fermanagh Highlands of nearby County Fermanagh. The rocks of the group sit unconformably on older rocks of the Shanmullagh Formation of the Fintona Group which are the local representatives of the Lower Old Red Sandstone. The top of the Dartry Limestone, the uppermost part of the group, is a disconformity, above which are the layered sandstones and shales of the Meenymore Formation of the Leitrim Group. The succession continues south and west across the border into the Republic of Ireland, though different names are typically applied.