Now little more than a village, Abernethy stands at the foot of its own steeply-climbing Ochils glen, right on the Fife border, looking out across the level carse to the junction of Earn and Tay rivers, just where the latter begins to widen to an estuary, 6 miles south-east of Perth. It is perhaps now most famous for its Celtic Round Tower, one of the only two remaining in Scotland, the second being at Brechin. These are tall, slender, tapering columns, free-standing and not part of church buildings, although sited in later kirkyards. The Abernethy Tower dates probably from the 9th or 10th century, with 11th century alterations. It is 72 feet high and only 8 feet in interior diameter, with walls 3 1/2 feet thick. There were six stages of timber flooring, and door and windows are in the Irish style. The modern clock is somewhat incongruous. These towers served the Celtic clergy as steeples, watch-towers against Viking invaders and others, and refuges. There are still 76 of them standing in Ireland.