Cardiff (pronounced /ˈkɑːdɪf ) 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.

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. Cardiff Urban Area covers a slightly larger area, including 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.

The Millennium Stadium (Welsh: Stadiwm y Mileniwm) is the national stadium of Wales, located in the capital, Cardiff. It is the home of the Wales national rugby union team and the Wales national football team but is also host to many other large scale events, such as the Super Special Stage of Wales Rally Great Britain, Speedway Grand Prix of Great Britain, boxing and many music concerts, including Tina Turner, Madonna, The Rolling Stones, U2 and the Tsunami Relief concert. It was built ready for Cardiff to host the 1999 Rugby World Cup.