astell Dolbadarn is located in North Wales at the foot of Snowdon and guards the road through the pass of Llanberis to Caernarfon. It is built on a rocky outcrop overlooking the pass and its round tower is supposed to have been built by Llywelyn the Great. The tower is all that now remains to be seen although there are the low remains of several rectangular outhouses. A modern curving staircase has been added to allow access to the first floor doorway. The castle can be visited free of charge.