Lady Isle Lighthouse is located on the island of the same name, around two miles southwest of Troon in the Firth of Clyde. The island once housed a chapel dedicated to Saint Mary.
Located on a low lying island the lighthouse warns of the Half Tide Rock and Scart Rock. It also aided navigation along the Firth and into Troon and Irvine harbours.
A pair of beacons were initially established around 1776 for Glasgow merchants.
One of the beacons was later removed, and the current lighthouse was built on the site of the beach. when lined up with the lighthouse it guided ships into a safe channel and anchorage. It also provided shelter for ships bound for Irvine.
The owners of Troon Harbour, Glasgow and South Western Railway Company, petitioned for a light, and this was approved by the Northern Lighthouse Board.
Lady Isle Lighthouse was established in 1903 to the design of David Alan and Charles Stevenson. It is unusual in design with a cross-shaped tower and external buttresses. An external staircase runs up the side of the tower. This staircase was originally made of cast iron and was later replaced with galvanised steel along with the balcony railing during its solarisation. The tapering beacon dates from 1776.
Construction of the lighthouse began in August 1902 and it came into operation on 27th January 1903.
The lighthouse was converted to acetylene around 1943. The fuel tank was removed during the modernisation process.
The lighthouse was initially powered by gas. A large cylinder housed the gas supply until it was converted to electricity around 2004. At the same time, it was converted to solar power by the Northern Lighthouse Board.
Lady Isle is owned by the Marquess of Ailsa. A bird sanctuary was run for a number of years by the Scottish Society for the Protection of Wild Birds.
The island can be seen from Troon harbour, where there is a lighthouse on the pier.