The Cairn a Leoghann Caidil is based at Seafield Tower, once the ancestral home of the Moutray family, the last of which died at the Battle of Sheriffmuir in 1715. The ruined redstone Tower still stands, though, a few miles outside the Fife seaport of Kirkcaldy
Of course, the site on which it stands has a much longer history. It's connection to Gaia is strong - in the summer, seals come to bask on the beach under its glare where once the Selkie met with their Fianna cousins. Seafield's isolation from the town of Kirkcaldy proper means that the area is spared from the pollution that city spits out, and the beach is also much cleaner than the beaches proximal to Kirkcaldy. It rests on the site of an ancient White Howler cairn, a Cairn that was subsequently claimed by the Fianna of the Damnomnii, the Irish pirates and settlers who swept eastwards from the Kingdom of Dalriada.