Skerryvore (from the Gaelic An Sgeir Mhòr meaning "The Great Skerry") is a remote reef that lies off the west coast of Scotland, 12 miles (19 kilometres) south west of the island of Tiree. Skerryvore is also the name given to the lighthouse on the skerry, built with some difficulty between 1838 and 1844 by Alan Stevenson. At a height of 156 feet (48 m) it is the tallest lighthouse in the United Kingdom. The shore station was at Hynish on Tiree which now houses a museum, operations being later transferred to Erraid, west of Mull. The remoteness of the location led to the keepers receiving additional payments in kind. The light shone without a break from 1844 until a fire in 1954 shut down operations for five years. The lighthouse was automated in 1994.
In pre-historic times the rocks that now form Skerryvore were covered by the ice sheets that spread from Scotland out into the Atlantic Ocean beyond the Outer Hebrides. After the last retreat of the ice around 20,000 years ago, sea levels were up to 400 feet (122 m) lower than at present. Although the isostatic rise of land makes estimating post-glacial coastlines a complex task, circa 14,000 BP it is likely that the reef was at the south western end of a large island consisting of the modern islands of Tiree and Coll and the surrounding land.