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 (700294). To the east and north of the house are the pleasure grounds,  concentrated in the valley of the Afon Llifon which flows through the park.

The pleasure grounds, dating from the early eighteenth-century, consist of lawns near the house, crossed by the river which has been canalised; a vista to the east with a lime avenue and fountains; a terrace behind the house with paths connecting with the path system in the Llifon valley, itself a major part of the pleasure  grounds; and plantations still containing several paths to the north, south and west. There are also small garden areas near the stable block and Children's Mill. Ornamentation has been concentrated on the river valley north-east of the house, almost the whole of it to the point where the river enters the park near the East Lodge, over 1km from the Children's Mill, containing various grottoes and caves, a hermitage, pets’ cemetery, and numerous water features. An icehouse is located on the south side of the canalised river (405556).
The three walled gardens (700295), linked by a tunnel, to the west of the house, and the nursery (400537), were also considered part of the ornamental garden.

Aerial reconnaissance on 15th July 2003 recorded parchmarks of buried pathways and formal features in the oval lawn fronting the house to the south.

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