Glynllifon Mansion is a grand neo-classical mansion set in extensive park and grounds (NPRN 86377). The house is constructed on the site of at least three earlier houses, the original predating a c.1600 rebuilding, with a second rebuilding in 1751 after which it was described as a moderate sized brick mansion. This was destroyed by fire in 1856, after which the current house was constructed. It was commissioned from Edward Haycock of Shrewsbury to stand on the cellars of the 1751 house. It was completed and fully furnished by 1846. It was extended to the west in 1889-90. The grounds are entered by a monumental arch (NPRN 31379) and the drives cross bridges before the house (NPRN 23774).

The house is three-storeyed and constructed of stone with rendered elevations under a slate roof. The design of the symmetrical 13 bay block is dominated by the central hexastyle pedimented portico, with a first floor loggia with Ionic marble columns. The front elevation is divided into paired bays flanked by pilasters ornamented with a Greek ffret pattern. There are numerous service and anciliary buildings associated with the house. These include: the icehouse (NPRN 405556); stable yard (NPRN 31380); workshop yard (NPRN 31381); a mill (NPRN 406301); a barn (NPRN 403747); a cattle rubbing stone (NPRN 309943), and estate housing (NPRN 404152).

In 1856, De Winton & Co. engineers of Caernarfon built a gasworks for Lord Newborough of Glynllifon House. The original gasworks contained two beds, each one containing a single retort, but was later enlarged. A second holder was added, both gasholders being 24' in diameter. Some drawings by De Winton survive. The gasworks appeared on OS maps from 1888 to 1959. The gas would have been used to light the house with gas.

In recent years the mansion has been converted to college use.

(CADW Listing Description) S Fielding 13/04/05
Source: Haslam, Orbach and Voelcker (2009), The Buildings of Wales: Gwynedd. Pevsner Architectural Guide, page 427.

RCAHMW, October 2009