The Castle can be visited
Rhuddlan Castle

Rhuddlan Castle, a ruin in Wales, is an example of medieval military architecture. Located in the town of Rhuddlan, it is among the early fortifications built under the command of Edward I to secure English rule in the region. Its design, featuring corner gatehouses, makes it an example of 13th-century castles.
History+
The construction of Rhuddlan Castle began in 1277 under the direction of James of St. George, commissioned by the English King Edward I. It was one of the first in a series of fortresses the king had built in Wales to consolidate his power.
Source: Wikipedia · Licence: CC BY-SA 4.0
This description draws on the facts documented in the linked Wikipedia article; Wikipedia content is licensed under CC BY-SA 4.0. Wording and editing: Mobile History.
Location: 53.2891, -3.4645