Achill island occupies an area of about 57 square miles. Its geography features a combination of glacial and coastal features. Achill’s location as one of the most westerly islands in Europe, and the climatic effects of the Gulf Stream, create a distinctive combination of flora and fauna.
One of the possible origins of the name Achill is the Gaelic word ‘acaill’, meaning eagle, and one of the earliest references to Achill came in 1235 when the Annals of Loch Ce refers to ‘Eccuill’ (Eagle Island). In later centuries travellers would remark on the golden eagles white tailed sea eagles on Achill, mainly on the peaks of Croaghaun. The last reported sighting of an eagle on Achill was in 1912. A number of rare bird species are still found on Achill, including the chough, golden plover and peregine falcon. Keel lake is often used as a resting point for barnacle geese during migration.