Pen Llystyn
Dolbenmaen, United Kingdom · built 80
Pen Llystyn, sometimes referred to as Pen Llys Tyn, was a Roman fort located to the north of Bryncir, between Porthmadog and Caernarfon in Gwynedd, north Wales. The fort itself stands on the east bank of the Afon Dwyfach.
Archaeological site data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).