Glynllifon mansion (nprn 26526) is located on the on the neck of the Llyn peninsula between Caernarfon and the village of Penygroes, about 1km from the sea. It is surrounded by vast parkland established in the eighteenth century and enlarged in the nineteenth, the house situated in the north-west part; the Afon Llifon flows through it. Records show that despite its size the park itself was extensively used for recreation. The park is roughly square in shape, the south-west corner elongated, and is surrounded by a continuous high stone wall about 10km long. There are several drives, many still in use though only the main west drive gives access to the house. There are lodges at five entrances: to the north (East Lodge), north-west (New Lodge), west (Grand Lodge, 31379), south-west (Cae Maenllwyd Lodge, 406382) and east (Upper Lodge). All entrances have arches in the wall, monumental on the west.

The park includes large areas of woodland and farmland, interspersed with each other to give several discrete areas of each. There is a broad swathe of woodland along the eastern edge of the park, farmland within it running up to the Llifon valley and the woods south of the house; in 1824 and 1828 part of this farmland, just north of Fort Williamsburg, was a deer park. North of the house, close to the farm buildings, is another block of farmland, with woods beyond it along the western edge. South of the house the pattern is more fragmented, with smaller areas of farmland and pieces of woodland, possibly originally shooting coverts, including narrow strips along most of the southern part of the western edge. The farmland was once mostly parkland but is losing its character as park trees die and are not replaced. Much of the woodland has now been planted over with commercial conifers and most of the original timber has been felled, though there are some survivors.

There are ponds and reservoirs dotted about the park (308973-4), some for agricultural use others to feed the water features in the pleasure grounds (86377). Walled gardens lie to the west of the house (700295). Other notable features include an eighteenth century fort (26460), a mausoleum (23010), ‘pleasing’ bridges crossed by drives before the house (23774), and the earthworks of long vanished tree-clumps (401184). The park was supplied from the large walled nursery to the south, later a pleasure garden (400537). An ancient monolith, Maen Llwyd (303384), stands beside the drive in the far south-western corner.
A complete mansion, Plas Newydd (16756), was enclosed within the park and in about 1900 it was restored and furnished with its own gardens.

Source:
Cadw 1998: Register of Parks and Gardens of Special Historic Interest in Wales: Conwy, Gwynedd & the Isle of Anglesey, 206-16 (ref: PGW(Gd)39(GWY).

RCAHMW, 23 June 2022