Arran, island, westernScotland, in the Firth of Clyde, part of Strathclyde region. The island is mountainous, and has an area of about 433 sq km (169 sq mi) reaching a maximum elevation of 874 m (2,866 ft), and the wild and rugged breakers of the northern shore attract both geologists and tourists. The island also is noted for beautiful glens and picturesque waterfalls. Places of interest include a ruined castle on the northern part of the island and the caves on the south-west in which the liberator of Scotland, Robert Bruce, is believed to have taken refuge from the English in 1307. The industries of the island include fishing, raising sheep and cattle, and growing oats and potatoes.