The island is 78 hectares (190 acres) in area and rises to a maximum height of 153 metres (502 ft) at the peak of Cruachan na h-àin ("midday hill").

[3] Muldoanich stands about 4 kilometres (2+1⁄2 mi) southeast of Castlebay, the main port on the island of Barra, and it is a prominent landmark for the approaching ferry and other craft.

[3] The name "Muldoanich" is probably the anglicised version of the Scottish Gaelic: Maol Dòmhnaich meaning[citation needed] "Duncan's rounded hill".

Writing in the 16th century, Dean Munro referred to the island as "Scarp" and it appears as "Scarpa" on Blaeu's atlas of 1654.

[3] Martin Martin refers to "Muldonish" in his 1695 voyage around the Western Isles, stating "about a mile in circumference; it is high in the middle, covered over with heath and grass, and is the only forest here for maintaining the deer, being commonly about seventy or eighty in number.