., Abergwyngregyn, Gwynedd, Wales

Map of Pen y Mwd location

A look into the field behind the houses off the main street in Abergwyngregyn, Aber, reveals a large grassy mound known variously as "Y Mwd", "Pen y Mwd", or "Aber Castle Mound". Others know it as as Llywelyn's Mound after the Welsh Prince Llywelyn ap Iorwerth, or Llywelyn the Great. The mound is circular, 22 foot high with a flat top 57 feet by 48 feet. Some say it's origin has probably no connection to Llywelyn and it has been suggested that it might be a fifth or sixth century A.D. mound built over the body of a local champion warrior lord. Another field of thought is that it was built by the Welsh Prince in the style of the Norman invaders. This seems to be the most likely. The top is very flat, with no sign of any masonry structure, so it was probably never refortified in stone once the original wooden castle had decayed. The mound is built largely of clay and has retained its sharp profile, but is suffering erosion. There is a hint of a protective ditch on the south side, but no sign of a bailey. A large oak tree sits atop the mound. Permission to enter should be sought from Tyn y Mwd, the 1st in a group of houses on the left close to the site.....