Aughinish (Irish: Eachinis),[2] also Aughnish, is a small island and townland in Oughtmama Parish of the Barony of Burren in north County Clare, Ireland.

[5] The British built the existing 0.5 miles (0.8 km)[6] causeway to County Galway to service their troops in the Martello Tower.

A wealth of monuments of archaeological interest attests of life on Aughinish since pre-historic times: Shell middens are located north-west and south of the island[8][9] A small cyst-like wedge tomb is located on the western side of the island, about 50 meters from its coastline[10] An early Christian church located on the south western shore of the island has been severely weathered.

A cillín (unconsecrated burial ground) is situated east of the church[12] Late medieval seaweed beds, a system used to farm seaweed, used as fertiliser and animal food, are located south of the causeway, and have been described as being "the largest and best preserved of its kind" "of national importance and "extremely vulnerable".

[13] A Martello tower, located at the most northern point of Aughinish,[14] is one of three Martello towers built on Galway Bay (the others being located in Finavarra and Rosaveal) in 1810, as advised by Major-general George Cathcart, to prevent the bay from being an easy landing point for a French invasion.