Colwyn Castle was a medieval castle near Llansantffraed in Wales. It was built on the site of a Roman fort. The castle was captured in 1196 by Rhys ap Gruffydd, who was campaigning against the Normans. It was rebuilt in 1242 by Ralph de Mortimer to protect the lordship of Maelienydd, which he had recently acquired.
The Borough of Colwyn was one of six districts of the county of Clwyd, north-east Wales, from 1974 to 1996.
It was formed under the Local Government Act 1972 from the following parts of the administrative county of Denbighshire:
The borough was abolished in 1996, when wales was divided into unitary authorities created by the Local Government (Wales) Act 1994. The area of Colwyn was split: a large part going to Aberconwy and Colwyn county borough, (soon renamed as Conwy), and the remainder going to Denbighshire unitary authority.
Colwyn is currently an electoral ward. It consists in part the Community of Old Colwyn with a total population of 4,566
Colwyn is twinned with Konstanz, Germany and Roissy-en-Brie, France.
Coordinates: 53°10′N 3°35′W / 53.17°N 3.58°W