Crug-y-Balog is an oval hilltop enclosure, 135m ENE-WSW by 94m, defined by a current field bank, whose dimensions, 4.0m wide, 1.5m external height and 1.0m internal height, suggest an earlier defensive enclosure: there are no signs of an external ditch.

(source Os495card; SN34NW1)
J.Wiles 23.07.04

Crug-y-Balog is a good example of an Iron Age enclosure, probably with an associated concentric field system on the north side, surviving as a fossilised set of banks in the present-day farming landscape.

T. Driver, 14 June 2007.