Walls of upper churchyard

The walls of the upper churchyard form an enclosure that measures approximately 75 meters from north to south and 45 meters from east to west. The wall stands about 4 meters high and 1.7 meters thick, constructed from rubble with dressed facing stones, some arranged in a herring-bone pattern. The inner face features occasional leveling courses, and there are two rows of putlog holes, with the lower ones near ground level and the upper ones approximately 1.5 meters above.

Some sections of the wall, particularly to the north, survive to wall-walk level and include a parapet that rises up to 1 meter high. The towers are approximately 5 meters in diameter, with the southeast tower rebuilt on Roman foundations and now incorporated into Stanley House, along with part of the south wall. The south gateway, which features two arches, follows the original design but has been rebuilt. A portion of the south wall is integrated into the rear of No 1 Market Square, while the southwest tower is largely incorporated into 19th-century buildings. Parts of the west wall are built into the tower of the church, and the northwest tower remains partly to wall-walk level.

There is a later insertion in the north wall that includes a gateway with a brick-lined arch. The northeast tower stands approximately 8 meters high from rock foundations in the lower churchyard and has bonding stones to the east for a former wall that flanked the quay. The east wall, which is about 1 meter thick, is mostly modern. Stone stairs lead down to the lower churchyard, which was created in the early 19th century.