The Castles and Town Walls of King Edward in Gwynedd refers to a UNESCO-designated site of patrimony located in Gwynedd, Wales.
In 1986, four castles related to the reign of King Edward I of England were proclaimed collectively as a World Heritage Site, as outstanding examples of fortifications and military architecture built in the 13th century.
Sites designated were:
- Beaumaris Castle, Anglesey
- Caernarfon Castle, Caernarfon
- Conwy Castle, Conwy
- Harlech Castle, Harlech
