The Cliffs of Moher (Aillte an Mhothair) mark the southwestern edge of the Burren region of County Clare in spectacular style. At their northern end, the cliffs start at a height of 120 metres at Hag's Head and reach their maximum height of 214 metres just north of O'Brien's Tower, eight kilometres away to the south. O'Brien's Tower is a round stone tower near the midpoint of the cliffs and was built in 1835 by Sir Cornelius O'Brien. This tower marks both the midpoint and the highest point of the cliffs of Moher. Living 200 metres below the tower and 50 odd metres out to sea is the spectacular 60-metre high sea stack called An Branán Mor. (Branaunmore) The name is very old and has a literal translation as the Big Prince or the Big Raven or Rook, probably named due to its shape when viewed from the sea as it looks like a large chess piece.
The stack was first (and the only) ascent to date was in May 1990 by Mick Fowler, Nikki Duggan and Steve Sustad, they climbed the north-west corner and seaward face of the stack in three pitches.