Caer Llugwy
Capel Curig, United Kingdom
Caer Llugwy, or Bryn-y-Gefeiliau, is the site of a Roman fort in a loop of the Afon Llugwy near Capel Curig in Conwy, Wales. It is notable in that there has been little development in the surrounding landscape: the valley in which it is situated being much as it was 2,000 years ago. It is a scheduled historic monument. The remains are on private land.
Archaeological site data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).