Llanddeiniolen, Caernarfon, LL55 3AE

Caernarfon (/kərˈnɑːrvən, kɑːr-/; Welsh: [kaɨrˈnarvɔn]) is a royal town, community and port in Gwynedd, Wales. It has a population of 9,852 (with Caeathro). Caernarfon Castle is a medieval fortress in Gwynedd, north‑west Wales. The first fortification on the site was a motte‑and‑bailey castle built in the late 11th century, which King Edward I of England began to replace with the current stone structure in 1283. The castle and town established by Edward acted as the administrative centre of north Wales, and as a result the defences were built on a grand scale. There was a deliberate link with Caernarfon's Roman past—nearby is the Roman fort of Segontium—and the castle's walls are reminiscent of the Walls of Constantinople.