Llanidan Hall is situated in the south corner of Anglesey on the shore of the Menai Strait. It lies within parkland (nprn 700033) and is surrounded by gardens (265387) which include the walled garden.  The house was built in the early seventeenth century and the walled garden is thought to be contemporary. 

The walled garden is situated on the south-west side of the house (15733). It is an irregular triangle shape bounded by a rubble stone wall about 3m high. The garden was originally roughly oblong. It was reduced on the south-east between 1783 and 1816 to the benefit of the open gardens before the house. There are square-headed doorways as well as a massively built stone archway opening from the main lawns. The walls were probably built of stone derived from the ruins of the monastic grange on which the site lies.

The interior was redesigned in the 1980s to be both ornamental and practical. The earlier layout, framed by a network of paths, was obliterated after the Second World War when the garden was ploughed. The northern part now has two rectangular formal areas. One is laid out with 32 small wood-edged herb beds, surrounded by a pergola with chain-linked wooden posts. The other, a 'physic garden' with two circular beds is surrounded by larger beds in geometrical shapes and with a similar pergola.

To the south-west of the herb gardens is a formal vegetable area, the layout superimposed on the earlier path system. In the centre, a container holds water and a tiny fountain. Parallel with the west wall is a canal fed by spring water from the 'holy well' just beyond the garden wall. Further south is an informal orchard area which includes many old fruit trees. There is also a new orangery and a restored glass-roofed potting shed.

Source: Cadw 1998: Register of Parks and Gardens of Special Historic Interest in Wales: Conwy, Gwynedd & the Isle of Anglesey, 18-22 (ref: PGW(Gd)46(ANG)).

David Leighton & John Wiles, RCAHMW  14 February 2022