The Ailsa Craig Lighthouse, is an active 19th century lighthouse located on Ailsa Craig, an island in the Firth of Clyde, just offshore from Girvan, South Ayrshire, Scotland.

Then, in 1990, the lighthouse was automated, and a refurbishment took place in 2001, when it was converted to run on solar power.

Ailsa Craig is also known as "Paddy's Mile Stone" as it lies halfway between the cities of Glasgow and Belfast.

Other wild life found on and around the island are a colony of grey seals as well as the occasional whale, and more commonly large basking sharks during the summer months.

In June 2018 the former lighthouse keepers' cottages, now derelict, were placed for sale by auction.