Grimsbury Castle

Grimsbury Castle is a slight univallate Iron Age hill fort situated within Grimsbury Wood between Cold Ash and Hermitage in Berkshire, enclosing about 8 acres of plateau. The defenses consist of a single bank and ditch with a combined height generally exceeding 2m, with two entrances featuring associated outworks. A natural spring within the enclosure has reportedly never run dry, and the rampart was extended southward to enclose it. Partial excavation by P. Wood in 1958-1960 yielded only three sherds of Early Iron Age pottery and a greensand quern stone fragment, leaving extensive unexcavated archaeological potential. Slight univallate hillforts are rare, with only about 150 examples surviving nationally.