Bencollaghduff (, meaning black mountain/peak of hags) at , is the 93rd-highest peak in Ireland on the Arderin scale, and the 115th-highest peak on the Vandeleur-Lynam scale. Bencollaghduff is situated near the centre of the core massif of the Twelve Bens mountain range in the Connemara National Park in Galway, Ireland. It is the 3rd tallest mountain of the Twelve Bens range, after Benbaun , to which it is connected by the northern col of Maumina; and after Bencorr , to which it is connected by a high southeast rocky ridge.