An astonishing sea stack that's lashed by foaming sea, Dun Briste is Mayo's top natural sight. Legend attests that St Patrick drove all the vipers from Ireland onto the stack on Downpatrick Head, leaving the mainland snake-free. Try to choose a clear day for a visit to amplify the visuals. You can drive most of the way up to the sea edge, but then you'll need to walk the last 400m or so. Dun Briste is 6km northeast of Ballycastle.
The sea stack was shorn from the mainland in 1393 by a severe storm that left poor unfortunates stranded upon it (later rescued). Indeed, the remains of buildings survive on the stack to this day. A viewing area has been constructed by a huge blowhole set back slightly from the cliff edge. It has numerous plaques detailing the history and folklore of the area. During storms, seawater is dramatically blasted through the blowhole.