Allnach, a rivulet of Inverness and Banff shires, rising in several head-streams on the north-eastern slopes of Caiplich (3574 feet), one of the Cairngorm Mountains. It runs about 13 miles north-eastward, partly on the boundary between the counties, and falls into the Aven, 1 mile S of Tomintoul. In its upper course it is known as Water of Caiplich.

(F.H. Groome, Ordnance Gazetteer of Scotland (1882-4); © 2004 Gazetteer for Scotland)