Foildarg is easily reached over the narrow rutted road starting at R891 482 D but pray you don’t meet anyone coming down and that you don’t fall into a pothole and emerge in China ! Its summit seems to be the location of Irelands highest off road track with jumps and even an oil storage tank. The summit pillar is kept company by a plaque to David Alan Addison who died in 1968, under what circumstances we can only wonder?
The hills here were formed around 300 million years ago when pressure from the African plate on the European plate caused an area of subterranean quartzite edged by old red sandstone to break through the limestone layer laid down by an ancient sea 50 millon years before that. The lithologies in this area are much like those of the Slieve Blooms with greywackes(which interestingly also make up about 30%of the landmass of New Zealand) and banded siltstones which provide graptolite fossils in areas . These can be seen near the main road outside Hollyford. Some local quarries also reveal a large amount of small local faults which are thought to be widespread in the area but mostly covered by glacial deposits. Linkback: https://mountainviews.ie/summit/660/comment/3566/