Grimsay () is a tidal island in the Outer Hebrides of Scotland.
Geography
Grimsay is the largest of the low-lying stepping-stones which convey the Oitir Mhòr (North Ford) causeway, a arc of single track road linking North Uist and Benbecula via the western tip of Grimsay. Until it opened in 1960, a ferry linked Carinish (on North Uist) with Gramsdale (on Benbecula), but could only operate at high tide. East of Grimsay lie several smaller islands including Ronay which was inhabited until 1931. a drop of over 15% since 2001 when there were 201 usual residents. During the same period Scottish island populations as a whole grew by 4% to 103,702. By 2022 the population was recorded as 149. Three generations of Stewart family built as many as 1,000 boats from three sheds on Grimsay. It is one of the best examples of a wheelhouse in the North Uist area but does not appear on Ordnance Survey maps.
right|thumb|A near infrared view of Grimsay Wheelhouse.
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File:Baghmor.jpg|Bagh Mòr on Grimsay, with Ronay in distance
File:Grimsaywheelhouse.jpg|A wheelhouse on Grimsay
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