There is an unnamed skerry about 100 metres (330 feet) to the north-east of the island, separated by Fint Sound.

Access can be problematic, as there are strong tidal surges in the surrounding strait, funnelled between Mainland and Rousay.

[6] Johan Blaeu's 17th century Atlas Novus records the name as Alhallow.

[11] The island's main attraction is Eynhallow Church, dating from the 12th century or earlier, and perhaps originally part of a monastery.

Eynhallow was believed to be the summer residence of the shape-shifting mer-people the Finfolk before they were driven away by a farmer from Evie, the Guidman o' Thorodale.