Local Authorities - High Water mark
This data shows the Local (Unitary) Authority boundaries for Wales. This dataset is derived from the OS OpenData Boundary Line product: http://www.ordnancesurvey.co.uk/oswebsite/products/boundary-line/index.html
DataMapWales
DataMapWales serves as a source for public sector data in Wales, providing a shared data platform to members of the public and public authorities.
https://datamap.gov.wales/