How to get there:
Diarmuid and Grainne's cave is located close the Gleniff Horseshoe Road nearby the old derelict school.
No official car park, but some spots where you can park the car are nearby.
The cave is only 400 meter from the road, but it must be said that this is almost 400 meter of vertical climbing. There is no official route, and the land you have to cross is privately owned. In such a case, you will always have to ask for permission. Also, the route is trecherous, and a group of students had to be rescued of the mountain before. The last part towards the cave is very steep, and a rope is available to help with the climb.
Diarmuid & Grainne's cave is Ireland's highest cave. It has a wide mouth, and the views are just spectacular. The cave itself has a wide entrance. There are a number of passages including the North facing tunnel which brings you to "the balcony" located in a cliff face.