St David's Cathedral Hall (formerly Chapel of St Mary's College) & attached Cloister Ruins

The building comprises St David’s Cathedral Hall, originally the Chapel of St Mary’s College, with attached ruins of a cloister to the south, and a southwest tower. It dates from the medieval period, likely the 14th century, although the roof was replaced in 1966.

The chapel is a four-bay structure built of rubble stone with ashlar dressings. It stands on a high barrel-vaulted undercroft. The exterior features tall, pointed windows deeply recessed above the undercroft plinth, flanked by purple ashlar buttresses that rise flush with the undercroft wall before stepping back. The buttresses were formerly topped with pinnacles and parapets, but now terminate under the 1966 roof. The windows retain fragments of original ashlar surrounds and Perpendicular tracery. The north side of the undercroft has six ventilation loops and a three-sided stair tower with a pointed doorway to the right, and the upper floor has one blank bay and three windows. A square stair turret is set into the northwest angle, rising to a flat cap above roof level from a broad masonry base with a low-pitched 1966 roof extending to the base of the southwest angle tower. The west front is of plain rubble stone with a low pointed door to the undercroft and a four-centred arched stair window above, featuring modern vertical mullions in the 1966 installation. A string course runs along the base of the plain rubble tower, which has a moulded flat parapet. A large stepped buttress rises from the former west wall of the cloister to the tower parapet.

The south front displays a nine-bay arcading of the demolished cloister at a lower level, with further fragments of the cloister’s east and west sides and the foundations of the inner wall also surviving. Above, there are three chapel windows and a blank bay where a tall building, originally connecting to the cathedral, formerly stood. A section of the building's three-storey east wall remains, featuring a pointed doorway, a first-floor window, and a small light above. To the left of the chapel's main entrance, a rubble stone arch, robbed of its ashlar, provides access from the former cloister to a flight of 14 broad steps leading to the chapel door. Remnants of the vaulting over the stairs remain. The chapel itself has been converted to a single hall space with a modern roof.

The east end wall is of rubble stone with a low four-centred door to the undercroft and a large window above.

The cloister ruins are a Scheduled Ancient Monument (Pe 444).