Flint Castle in Flint, Flintshire, was the first of a series of castles built during King Edward I's campaign to conquer Wales.
The site was chosen for its strategic position in North East Wales. The castle was only one day's march from Chester, supplies could be brought along the River Dee and there was a ford nearby across to England that could be used at low tide.
Wikipedia https://en.wikipedia.org/wiki/Flint_Castle
Address CH6 5, United Kingdom
Coordinates 53°15'6.35" N -3°7'47.667" E