Architectural Features
Tower built c1071 for Robert d'Oilly to guard the north-west angle of Oxford Castle bailey and serve as the bell tower to the castle Chapel of St. George. Walls at ground level 9' thick. Ramparts with cruciform arrow slits in round- arched settings. Later square headed mullioned windows. Ramparts with cruciform arrow slits in round- arched settings. South east stair turret with doorway which would have given access to former curtain wall. Interior has wide arch with imposts, formerly to nave. Ground floor appears to have been in use as a tread mill having wide floor boards worn with two concentric rings. Timber newel stair gives access to floors, most with old timber beams. St. George's Tower is a rare piece of stone military architecture surviving from the conquest period and was probably the earliest stone building in the Castle.
St. George's Chapel Crypt Crypt, now beneath D Wing of Oxford Prison. c1074, probably rebuilt in 1794 and possibly again in 1848. Stone. 3 1/2 bays long by 3 wide. Renewed groin vaults spring from original columns with crudely carved chevron design Romanesque cushion capitals. Cobbled floor. The church itself projected eastwards from the base of St. George's Tower and probably had an apsidal end. St. George's began as a collegiate church for secular canons, founded and endowed jointly by Robert d'Oilly and Roger d'Ivry. Amongst the canons were notably learned men including Walter Map, Robert of Chesney and historian Geoffrey of Monthmouth whose presence may have contributed towards the establishment of the University in the town.
The Well House, sunk in the top of the motte, has an early C13 stone vault with chamfered ribs; it is 4 ft in diameter. Above the entrance to it are three C16 reset stone shields of arms somewhat weathered. The site of the castle suffered in C17 and was mostly cleared when the prison was built in 1805.
The well house is an artificial structure on top of an artificial mound. So this is not a traditional excavated well, but one built up at the core of the motte of the castle, to ensure that those in the (long vanished) tower could access fresh water from below natural ground level. The well house is listed grade 1 (list entry number 1369493).
The Mound dates from the building of the castle, in 1071. Two trees are growing near the top of the Mound; one, plus the steep slope on the side of the Mound, can be seen in this photograph. The spire of Nuffield College is just the other side of New Road.