Diarmuid and Grainne’s Cave is located on the the north face of Benbulbin, the majestic table-top mountain at the heart of North County Sligo. The cave is grand and dramatic and it is thus an suitably fitting backdrop to the story of the pursuit of Diarmuid and Grainne, the soldier and princess heroes of the Fenian cycle of Celtic mythology. Their flight from the the jealous and aged Fionn mac Cumhaill saw them hide in the hills of Benbulbin and, according to lore, in this cave. Numerous sites around Connaught have claimed the name of the doomed couple but it is upon the hills of Benbulbin, above the cave, where Diarmuid was eventually deceived and killed. A fitting cave for a hide-out but you cannot run from a demi-god such as Fionn mac Cumhaill!
Despite being one of Ireland’s highest caves, the sedimentary deposition that led to mountain building was laid-down in the sea. The shells and sea fossils that dot the limestone outcrop on the roof of the mountain above the cave mouth are testimony to this and it is from here that Sligo derives it’s Irish name, Slí Geach or Shelly Place.
Any time I take friends to Diarmuid and Grainne’s Cave I always tell them it’s just 400 meters from the car. This is true of course but it’s only on arrival it can be seen that most of those 400m are vertical!
In terms of beauty the cave system may not compare to other local caves but it is of significant size and it’s setting is spectacular. I have been up here numerous times and the view changes on each visit. Sometimes the clouds move in obscuring the way down from view, other times rainbows form outside the entrance.
There are few calcite formations or decorations in Diarmuid and Grainne’s Cave, however there are a number of interesting passages including the spectacularly sculpted North facing rift tunnel that leads to a balcony in the cliff face (above). Despite how suddenly the initial chamber closes in, the large South chamber, accessed via a keyhole squeeze in the back wall, is an unexpectedly pleasant surprise. At greater depth is the Lower Series chambers, which I have not yet seen, reached at by a ten meter pitch that leads to broad passagesways.
NOTE: As of April 2015 access to the cave via the land at the old schoolhouse is denied by the landowners.