Diamond Hill is the classic Connemara walk: a looped trail of about 7 km from the Connemara National Park visitor centre, rising to 445 metres with panoramic views over the Atlantic, the Twelve Bens, and the islands. The summit path is rocky and well-maintained; the walk takes two to three hours at a comfortable pace. On clear days you can see as far as the Aran Islands and the mountains of Clare.
The hill gets its name from the quartzite boulders on its flanks, which flash in sunlight like cut stone. The path crosses through heath and bog, passing streams and small loughs. It is consistently ranked among the best accessible mountain walks in Ireland and is busy in summer, but the size of the landscape makes the crowds irrelevant once you're on the hill.