Another castle on the Welsh border, the castle was established by the Normans in 1087CE. The castle was built to overlook the river Usk. A stone keep replaced the original wooden building in around 1100. In 1175 the castle was the scene of a massacre when a group of Welsh nobles were killed there after being lured there under false pretences by William de Braose.
The castle was expanded in the 13th and 14th centuries. By the 15th century however, the castle was falling out of use. It was slighted by orders of the King in the Civil War to stop it being used by Parliamentary forces.
By the 18th century the castle ruins were beginning to attract visitors. A hunting lodge was built atop the motte in 1819. The building now houses the town's museum.
