Barton’s Hole

County Sligo

Barton’s Hole is exceptional in being both a mine and a cave. The entrance, a reasonable sized pothole, widens after a few meters of depth until the walls suddenly drop off at the sides revealing a massive chamber. While certainly a natural hole, it has undergone engineering, most likely with the removal of in-fill from above and below (Barry, 2015). Furthermore, near the top of the pothole, laddered horizontal mine workings can be accessed.

An abandoned mine cart

After the dramatic descent, it becomes very obviously a mine. The mine’s preservation is quite good, with core samples lying around, many laddered shafts, railway tracks throughout and even an old cart and tools left abandoned. You can almost feel the presence of the last miner to work here – on his last day – deciding not to bother push the cart to the exit and leaving it half full of baryte!

This mine is essentially connected to the better known and more easily accessible Glencarbury Baryte Mine, and is part of that system. This was initally operated by a Mr. Barton (Hallissy, 1923). It was worked since 1878 and over the proceeding hundred years it continued to have periods of great productivity interlaced with long periods of cessation. In the later half of the 20th century it was significantly modernised and it is possible that the great ‘entrance’ shaft was used for machinery access or as pulley system for removing baryte (MacNamara, 2013).

A typical low-level passageway that gradually becomes a higher-than-waist level of water!

However, since being finally abandoned in the 1980s, some of the mine passages have collapsed (although I imagine this was done intentionally), closing horizontal and ground access to this section of the mine.

Barton’s Hole contains many noteworthy things that are not found in the Glencar mines

We had little time to explore it all but it was clear that in some parts of the mine, the workers cut into some natural caverns. Perhaps the least dramatic feature but the most fascinating is the presence of perfect cave peals in one ‘mine’ passage. Cave pearls are extremely delicate cave formations in which calcite is precipitated from running water and forms around a nucleas of dust or dirt. The constant flow of water (such as in a dripping pool) causes them to become well rounded. They can take thousands of years to form and can be destroyed by even slight disturbance or an influx of impurities. Despite this, the miners who broke into this section of natural cave and subsequently worked it, remarkably avoided disturbing the formation and it can be seen in pristine condition.

Cave pearls (in a mine!)

There are numerous laddered levels and open shafts in the ground here as well as partially flooded passages. I particularly liked seeing the hand-painted wooden signs at the bottoms of ladders which read “Escape Manway”. We did not have enough time to explore it all but with what we saw it is nonetheless very impressive and, combined with Glencarbury mine, stands as one of Ireland’s most impressive monuments to our mining heritage.

WARNING: While most newly explored caves pose a greater risk than well-trodden ones, parts of the shaft walls at Barton’s are exceptionally loose due to the presence of delicate baryte and its history of being physically engineered as an industrial mine. People without advanced SRT rope work, rigging, rescue skills and appropriate PPE need to STAY AWAY!! An accident here will put your life and those of potential rescuers at risk!


Barry, P., 2015. The Undescended Pit. Descent, 245, 16 – 18.

Hallissy, T., 1923. Barytes in Ireland. Memoirs of the Geological Survey of Ireland. Dublin: Stationary Office.

MacNamara, S., 2013. Barton’s Hole. Shannon Group Web. 23 April 2015.

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