Bodelwyddan Castle
Located in Denbigh county, just a few kms from Abergele, Bodelwyddan Castle is a perfect Welsh example from the 19th century, surrounded by a wonderful park (200 hectares).
In the 1980s it was bought by  Clwyd County Council who then transformed it into a museum and art gallery (open to the public).

Look at the Bodelwyddan Castle's web site for more information