Carmarthen (UK: kər-MAR-dhən, locally kar-; Welsh: Caerfyrddin kaːɨrˈvərðɪn, 'Merlin's fort' or possibly 'Sea-town fort') is the county town of Carmarthenshire and a community in Wales, lying on the River Towy 8 miles (13 km) north of its estuary in Carmarthen Bay. At the 2021 census the community had a population of 14,636, and the built up area had a population of 16,455. It stands on the site of a Roman town, and has a claim to be the oldest town in Wales. In the middle ages it comprised twin settlements: Old Carmarthen around Carmarthen Priory and New Carmarthen around Carmarthen Castle. The two were merged into one borough in 1546. It was the most populous borough in Wales in the 16th–18th centuries, described by William Camden as "chief citie of the country". It was overtaken in size by the mid-19th century, following the growth of settlements in the South Wales Coalfield.
