Situated at the eastern end of an ancient and Roman road which passes above Abergwyngregyn and its sister castle of Pen-y-Mwd, as far as Segontium (modern Caernarfon) passing through the Bwlch y Ddaufaen (the Pass of Two Stones - see collection Romans in the Conwy Valley by Maldimo52). Not a lot is known about this castle mound, which is believed to have been built by Maelgwn Gwynedd to control the lowest crossing point of the River Conwy. Now damaged by quarrying the stone during the construction of the modern Baily Bridge across the river.