Plas Boduan (nprn 26062) is a large mansion in the Georgian style first built in 1736. The house is surrounded by gardens and grounds (301627) within which are two walled gardens.

The gardens lie a short distance to the north-west of the lodge at the park entrance. They are two long rectangular enclosures, conjoining on the east and west, long axes slightly east of north by south. They do not appear on the 1816 Ordnance Survey  manuscript  map, but were in place by 1889.

The east garden is the larger, almost twice the size of its neighbour, with a mortared stone wall around it, originally about 2.8m high but later raised on the east side to about 3.5m, and again on the north side to about 4.5m. The north and east walls are brick-lined, the west wall brick throughout, and the south wall only stone. There are entrances in the north wall, and in the south wall (now blocked), but a wooden door remains in this wall a little to the west. In the centre of the west wall a doorway leads into the west garden. The interior has no remaining features and is used as pasture. Some wall-trained fruit trees remain in place, though these appear not to be ancient. Early Ordnance Survey maps (1888) portray a layout of perimeter and cross paths dividing the interior into seven plots. There is now no trace of this. The interior is now under grass and there are buildings in the north-west corner. 

The west garden is now privately owned, belonging to a house converted from former garden buildings, including a small, two-storey, stone-built octagonal building, which is built through the north wall at the point where the two gardens join, and is now the core of the house. There are lawns, borders, a modern greenhouse and a wide gravel drive. The stone surrounding wall is mostly intact averaging about 2.5m high, higher on the north side. The garden once contained several free-standing glasshouses at its north end. Inside the garden are some fruit trees and wall fruit recently maintained as bush trees; some were once trained as espaliers. This garden's portrayal on the 1888 map suggests it may originally have been an orchard. There is also a sundial (probably imported) and a slate water-tank just inside the entrance through the west wall. 

Sources:
Cadw 1998: Register of Parks and Gardens of Special Historic Interest in Wales: Conwy, Gwynedd & the Isle of Anglesey, 152-5 (ref: PGW(Gd)17(GWY)).
Ordnance Survey first-edition six-inch maps: Caernarvonshire XXXII SW & XL NW (1888); third-edition (1918).
Additional notes: D.K.Leighton.

RCAHMW, 17 June 2022