Cardiff Welsh: Caerdydd is the capital, largest city and most populous county of Wales. The city is Wales’ chief commercial centre, the base for most national cultural and sporting institutions, the Welsh national media, and the seat of the National Assembly for Wales. According to recent estimates, the population of the unitary authority area is 324,800, while the wider metropolitan area has a population of nearly 1.1 million, more than a third of the total Welsh population. Cardiff is a significant tourism centre and the most popular visitor destination in Wales with 14.6 million visitors in 2009.

The city of Cardiff is the county town of the historic county of Glamorgan (and later South Glamorgan). Cardiff is part of the Eurocities network of the largest European cities. The Cardiff Urban Area covers a slightly larger area outside of the county boundary, and includes the towns of Dinas Powys, Penarth and Radyr. A small town until the early 19th century, its prominence as a major port for the transport of coal following the arrival of industry in the region contributed to its rise as a major city.

Cardiff was made a city in 1905, and proclaimed capital of Wales in 1955. Since the 1990s Cardiff has seen significant development with a new waterfront area at Cardiff Bay which contains the Senedd building, home to the Welsh Assembly and the Wales Millennium Centre arts complex.

Sporting venues in the city include the Millennium Stadium (the national stadium for the Wales national rugby union team and the Wales national football team), SWALEC Stadium (the home of Glamorgan County Cricket Club), Cardiff City Stadium (the home of Cardiff City football team and Cardiff Blues rugby union team), Cardiff International Sports Stadium (the home of Cardiff Amateur Athletic Club) and Cardiff Arms Park (the home of Cardiff Rugby Club). The city is also HQ of the Wales Rally GB and was awarded with the European City Of Sport in 2009 due to its role in hosting major international sporting events.