Ailsa Craig is a now uninhabited volcanic island covering 99 hectares (240 acres) in the outer Firth of Clyde, 16 km (9.9 mi) off the south Ayrshire coast.
The island is the source of three rare types of blue hone granite, harvested by the licence holder as required for the manufacture of curling stones for use in the Scottish sport of curling. But it is perhaps best known as a designated Site of Special Scientific Interest and a Special Protection Area for its populations of breeding seabirds.
There are thought to be around 73,000 of these, including the third largest gannetry in the UK, with colonies of guillemots, razorbills, black guillemots and an increasing population of puffins.
The island is only accessible by boat. Tours operate from Girvan and Campbeltown in summer when sea and weather conditions are good. Although these trips often feature a short amount of time on the island itself, the bird colonies are, in any case, best viewed from the sea. There is also an historic lighthouse, still operational, dating back to the late 19th century.