Only a small section of the Romano-British city wall, on the inside of the medieval tower where it had not been re-faced, was examined; it was made of the characteristic courses of large flints found elsewhere along the circuit of the wall. A single Romano-British tile was found in the face of the wall and, lower down, an offset was visible; in the post-Roman period, the face of the wall had been buried by silt and later the wall of the Medieval tower was straight-jointed against it.