It is difficult to pinpoint precisely when Carndochan Castle was built, but it is thought to have been built in the 13th century by Llywelyn ap Iorwerth (Llywelyn the Great). Although only remnants of the castle remain today, the tower ruins are typical of the castles of Llywelyn and his grandson Llywelyn ap Gruffudd.
The castle stands on the summit of a rocky hill about two miles from the village of Llanuwchllyn and has magnificent views of the Bala area.
The old cantref of Penllyn, where Carndochan stood, was relatively far from the heart of Gwynedd. The princes of Gwynedd and Powys grappled over the area for centuries. Carndochan was strategically important in controlling the route into Gwynedd, a route historically used by enemies of the area’s princes.
Edward I travelled the country in 1283-4 and may have visited Carndochan and other castles on his campaign. However, there is little to no documentary evidence about the castle itself, and much of its secrets has been revealed by archaeological work.
Archaeological excavations at the site have resulted in several finds which give us a broader picture of the history of Carndochan Castle. A decorated glass bead dating from the Iron Age was discovered at the site. Therefore, it is likely that the castle’s location was defended in prehistoric times.