The limestone cave network is the source of three rivers whose source under the Cuilcagh Mountain forms the Cladagh River. The name derives from a limestone arch on the river at Cladagh Glen.
Visitors start the tour, which lasts about an hour and a quarter, from the visitor centre with a walk through the Marble Arch National Nature Reserve. From there, the first glimpses of the caves come in a boat that travels for about 10 minutes into the heart of the Marble Arch underworld, allowing visitors to see the stunning and otherworldly cave formations with stalactites, stalagmites and pillars throughout the chambers. One of the best-known formations is the Porridge Pot, which took an estimated 50,000 years to form.
After the boat journey, the tour continues on a winding path for about a mile through the caverns, with a flight of 160 steps up at the end.
The Marble Arch Caves were explored in full for the first time in 1895 when French caver Edouard Martel and Dublin scientist Lyster Jameson ventured into the cave by candlelight. The caves were mostly forgotten until 1985 when the pathway and lighting were erected. Now the Marble Arch Caves are part of a geopark that includes Cuilcagh Mountain and several forests, allowing visitors to enjoy nature above the ground as well.
Heavy rainfall makes the cave river swell, and high water levels inside the cave may make it inaccessible so it’s a good idea to check on the day before travelling to see whether the caves are fully open.
