Garth Celyn for the benefit of present and future generation (sic), to create a lasting memorial to the Princes and their achievements". The Trust identifies modern Garth Celyn as the site of the royal llys (palace) in the 13th century and the centre of government before the Conquest, and suggests that many notable events in Welsh history occurred here. There are local traditions pointing to Pen y Bryn / modern Garth Celyn / Bryn Llywelyn as the site of the royal llys. These claims are part of a local disagreement. A royal llys of the Welsh princes was located at Abergwyngregyn; in November 1282 Prince Llywelyn ap Gruffudd dated letters to the archbishop of Canterbury at "Garth Kelyn". In 1537 John Leland reported "The Moode, in the paroche of Aber otherwise Llan Boduan, wher Tussog Lluelin uab Gerwerde Trundon (sic) had a castel or palace on a hille by the Chirch, wherof yet parte stondith." A high-status structure, associated with 13th and 14th century material and thought to be the royal llys with its domestic and administrative buildings, has been found in the valley bottom, on the other side of the river and some 185 metres from Pen y Bryn. It is by the mound known as y Mŵd, near which in 1811 visible remains were locally supposed to be the palace of the Welsh Princes. Notes References Notes External links Abergwyngregyn Houses in Gwynedd History of Wales Medieval Wales Scheduled monuments in Wales Grade II* listed buildings in Gwynedd