The Frith is a small univallate Iron Age hillfort to the north of Silchester, Calleva Atrebatum, Roman town. A single bank covers all sides apart from the south east, and is at the most about 5 feet high on the western edge. A ditch is also traceable for the length of the bank, although at varying states. The area to the North and Northwest is partially wooded. A local footpath crosses the site East to West. The site slopes from approximately 90m to 95m in the West, with the summit of the unnamed hill (102m AOD) approximately 500m to the Southwest. Close by to the South lies a Roman road heading into Calleva Atrebatum.