Grennan Hill

This oval fort is situated at about 500 ft OD on the summit of a rocky hillock; it measures 152 ft NNW-SSE by 62 ft transversely. It is defended by a partly rock-cut ditch, 35 ft broad and 16 ft in maximum depth, starting at the brow of the steep slope on the W, passing round the E side to end on the cliffs in the S. Soil from the ditch forms a rampart above the counterscarp, while a parapet mound crowns the scarp in the N.
A well-defined approach enters into a slight hollow at the lowest point of the interior. An ill-defined outwork flanks the S side of the approach. In the interior are three slightly hollowed circular areas which may be hut sites.
RCAHMS 1920, visited 1913; R W Feachem 1956