Barra Head Lighthouse identifies the southern entrance to The Minch, roughly halfway between the Eilean Glas and Rinns of Islay lighthouses. The stone tower stands on the west side of the island, at the top of a very steep cliff, making the light above sea level, with a range of . There is no shallow water west of Berneray to break the blow of the Atlantic storms and small fish are sometimes thrown onto the grass on the cliff top. In 1836 Sir Archibald Geikie recorded the movement of a block of gneiss across of ground during a violent storm.