Glynllifon is an old estate which belonged to the Barons Newborough, near the village of Llandwrog on the main A499 road between Pwllheli and Caernarfon in Gwynedd, Wales. The original mansion was until recently a privately owned hotel.

Baron Newborough is a title that has been created twice in the Peerage of Ireland; both titles are extant. The first creation came in 1716 in favour of George Cholmondeley, later 2nd Earl of Cholmondeley. See Marquess of Cholmondeley for further history of this creation.