The site of Castle Hall is on the east side of Milford Haven, overlooking the Haven itself and an inlet known as Castle Pill (nprn 21726). The present house is a modern, utilitarian structure built on part of the earlier house platform, after the demolition of the mid-nineteenth century house (that replaced the late eighteenth century building) in the 1930s. Its early nineteenth century garden incorporates some late eighteenth century features including substantial terraces. There are fine approach entrances, a grotto, lake, and further terracing with a range of glass and an enigmatic garden structure at one time referred to as a pinery.

Formal gardens, small rectangular beds with a central circular bed, existed by 1769 (when they are portrayed on an estate map), descending west of the house towards a pool and the shore. An enclosed orchard then lay to the north of the house. There followed a history of landscaping spanning the next 150 years. The present, early-19th-century gardens, include two substantial terraces associated with the house. There are fine entrances at the approach and elsewhere, a grotto and a lake with islands. There is also further terracing with a range of glass and an enigmatic garden structure formerly referred to as a 'pinery'. By the early nineteenth century the slopes around the house were described as ‘charmingly wooded’.

The grounds are rectangular on plan, long axis east by west. The house site, stable block and gardens together occupy a little more than 10 acres, of which a quarter acre is the lake. The gardens are formed in a now dry, shallow valley which slopes from the house down towards Castle Pill, giving the garden a mostly west-facing aspect. Below the house platform are steps leading to two terraces. On the north side of the lower terrace steps give access to the main garden area. Immediately below and to the west of the lower terrace is the tennis court and below that again is the lake.

The main entrance to the house is off Castle Hall Road to the north (formerly a drive) where the boundary wall rises to above 4.5m. At the entrance to the drive is a wide masonry carriage arch, nearby the remains a gatehouse, and further arches are to the south and north of the entrance (22534). At the turn of the twentieth century there were three vehicular entrances to Castle Hall, two from the west and the third from the east. Though early surveys give very little indication of their exact route, two lodges are shown on early OS maps, one to the north (western drives) and another on the east (22533). The area between the lodges is shown as parkland in the nineteenth century but is now a housing estate.

Also present is the site of the orangery, to the east of the gate, now marked by low brick walls which included a heated wall, and nearby the 'pinery' (22536). To the north of the tennis court is a series of three semicircular arches within a retaining wall, that lead into a groin-vaulted 'grotto', together over 48m long, supporting a terraced garden area above. A range of glasshouses is built against the northern (south-facing) boundary wall.

Sources:
Cadw 2002: Register of Parks and Gardens of Special Historic Interest in Wales, Carmarthenshire, Ceredigion and Pembrokeshire, 180-85 (ref: PGW(Dy)16(PEM)).
Ordnance Survey County Series six-inch plan: sheet Pembrokeshire XXXIII.7 (first edition, 1862).

RCAHMW, 9 June 2022