Into the dark underworld with Alice, Donna and Heidi at the 5,000+ year-old Carrowkeel megalithic tomb complex on top of a hill south of Sligo, Ireland. There are dozens of tombs of all sizes here, but three larger cairns, known as G, H and K, are open and large enough to enter. (Cairn H has partially collapsed, so we passed on that one).
Cairn G features a slab of rock blocking the entrance with a vertical slit carved In it, which aligns with the rising sun every Oct. 31, sending a shaft of sunlight into the depths of the tomb.
