Caldey Island, off the coast of south Pembrokeshire, has been home to a religious establishment since the sixth century, and a Benedictine priory was founded in 1136 (nprn 245). Following the Dissolution, developments culminated in a mansion built on the north side of the priory complex in the early nineteenth-century (311).
The gardens associated with the priory and the mansion house lie to the north and east of the priory complex. They occupy the level ground in the immediate vicinity of the buildings and a small, narrow valley running down north from them, the former gardens here tapering to a point about 200m north of the priory. The nineteenth-century garden partly overly the earlier, medieval, garden (265323). The site is a complex one occupied over a very long period and it is hard to be certain what is original and what has been restored. 

The nineteenth-century garden was created by Thomas Kynaston to accompany the mansion that he built in 1800. It occupies the level ground to the north of the mansion site, and the valley to the north. A rectangular area north of the house, now much overgrown, is bounded on the north by a wavy ha-ha and on the west by a stone wall. In the centre is a fallen sundial.
The valley to the east was laid out as a garden with five stone-walled compartments conjoined in linear fashion, bounded on the east by a hedgebank and a lane leading to the priory. Three of the enclosures incorporate the medieval ponds, a fourth the mill ruins. The fifth, lowermost, compartment is an elongated triangle containing a small pond of more recent date and, just outside the garden to the north-west, are the ruins of a small rectangular cottage.

The compartments are now mostly overgrown with trees but the 1887 map shows them laid out with paths and planted with mixed deciduous and coniferous trees; those between the house and the mill were more ornamented than those to the north, in which there was informal tree planting and a walk.

Sources:
Cadw 2002: Register of Parks and Gardens of Special Historic Interest in Wales, Carmarthenshire, Ceredigion and Pembrokeshire, 168-71 (ref: PGW(Dy)60(PEM)).
Ordnance Survey First-Edition six-inch map: sheet: Pembrokeshire XLIV.NE (1887).

RCAHMW, 11 May 2022