The ruins of Boulston Old Hall are situated on a small inlet on the north shore of the Western Cleddau estuary, to the south of the hamlet of Boulston, on a site with origins in the medieval period (nprn 21647). They are associated with a walled garden of four compartments with fishponds to their north. The grounds overall form a triangle, from the shoreline on the south-east narrowing to a point at the junction of tracks on the north-west. Garden remains lie around the ruined house. They are abandoned, ruined and overgrown but their structure and much of the surrounding walling remains. No internal layout or planting survives.
The gardens are believed to date from the second half of sixteenth century.

The main feature is a walled terrace which lies between house and shore. It is 70m long and 8.5m wide surrounded by walling up to 3.5m high, revetted on the seaward side, a parapet wall above it. Towards the west end is a wide, arched, entrance gap inserted later, a gate opposite leading to the walled area east of the house. To the west of the terrace a smaller walled bay may have been an entrance court. To the east of the house, north of the terrace, is a third enclosure, its walls about 3m high. To the north of the west end of the house are the remains of the fourth compartment, its residual walls on the north and east sides rising to 3.5m.

Beyond the immediate vicinity of the house, ancillary features linked to it include Ash Wood, mixed woodland to the north and east; an old, stony track, flanked by low rubble stone walls, running from Boulston Farm southwards through the wood to the shore; and another, similar track running south-eastwards and then eastwards at the northern end of the wood, and crossing the stream through the wood over a small arched stone bridge. The stream flow is interrupted by two, probably ancient, ponds, the upper, smaller one is of irregular shape with an earthen dam along its south side, the larger one below it.
The present visible layout of the walled compartments is shown on the Ordnance Survey map of 1899 (revised 1888).

Sources:
Cadw 2002: Register of Parks and Gardens of Special Historic Interest in Wales, Carmarthenshire, Ceredigion and Pembrokeshire, 164-7 (ref: PGW(Dy)69(PEM)).
Ordnance Survey 25-inch map: sheet Pembrokeshire XXVIII.13 (first edition, 1887).

RCAHMW, 9 June 2022