The present Chester Castle is largely Thomas Harrison's group of county buildings, dating from 1788-1822, and including the courts and the Shire Hall. The main medieval survival is Agricola's Tower, a three-storey tower on a rectangular plan, with a doorway to the south. The tower dates from the 12thc., but there was a fire in 1302, after which the lower room was remodelled entirely. Romanesque interest centres on the 2nd-storey chapel. This is a single space vaulted in two rectangular bays with quadripartite rib-vaults and an altar at the east. The present author was unable to gain access, and this report is based on what can be seen of the chapel through the grille that closes it off. For the guidance of future researchers, the chapel is now the Regimental Chapel of the Cheshire Regiment, and entry is controlled by the staff of the Military Museum, also on the castle site, who require at least two weeks' notice in advance of any visit.