Hemmed in by recent waterfront development the Roman courtyard building at Cold Knap, Barry, lies very close to the sea and once overlooked salt marsh and the nearby anchorage of Barry Harbour. Excavated in 1980-81 by the Glamorgan-Gwent Archaeological Trust, and acquired by the local authority thereafter following the considerable public interest in its discovery, this enigmatic building has been preserved for future generations to admire. Although it may have been a maritime establishment to oversee trade at the nearby small harbour, the excavators thought it more like to be a mansio, or Roman guesthouse, with the small rooms arranged around the open courtyard (now lawned) providing ideal accommodation .

T. Driver, RCAHMW, Sept 2011.

On the shore of the Bristol Channel. In 1960 building operations revealed and later destroyed the walls of a sunken rectangular structure of dressed stone. It measured 6.4 m by 5.8 m; the walls were 0.6 m thick and survived to a height of 1.2 m. The interior had a cobbled floor on which was a thick layer of debris containing building stones and Roman tiles. Near the building were found a few fragments of Roman pottery including a sherd of 2nd-century samian ware. `Human remains? are recorded as having been found at this site in 1866.

Source: RCAHMW., 1976. An Inventory of the Ancient Monuments in Glamorgan, Volume I: Pre-Norman, Part II, The Iron Age and Roman Occupation. Cardiff: HMSO 110

Lorna Leadbetter-Jones, for RCAHMW March 2013

A late 3rd century AD Roman building which may represent a 'mansio' (a building used for the comfort of travellers). This would accord with its location on the north side of the Severn Estuary directly opposite the estuary of the River Parrett, from which a road led to the Roman town of Silchester. No road on the Welsh side has so far been identified however.

The lower walls and foundations represent a rectangular building complex measuring externally 33m north-west to south-east by 28m, containing at least 18 rooms of varying sizes, set about a courtyard 20.5m by 12m with, possibly, a centrally-placed garden area. It has now been laid out for public display.

Source: Evans et al. 1985 (Britannia 16), 57-126.

RCAHMW, November 2010.