The Millennium Stadium (Stadiwm y Mileniwm) is the national stadium of Wales, located in the capital city, Cardiff. It is the home of the Wales national rugby union team and also frequently stages games of the Wales national football team, but is also host to many other large-scale events, such as the Tsunami Relief concert, the Super Special Stage of Wales Rally Great Britain, the Speedway Grand Prix of Great Britain, and various music concerts. It was built to host the 1999 Rugby World Cup.

The Millennium Stadium is owned by Millennium Stadium plc which is a subsidiary company of the Welsh Rugby Union (WRU). The stadium was designed by a team led by architects Bligh Lobb Sports Architecture, who merged to become HOK Sport Venue Event, which would be renamed Populous in early 2009. WS Atkins were the structural engineers, and the building contractor was Laing. The total construction cost of the stadium was £121 million, of which the Millennium Commission funded £46 million.

The stadium opened in June 1999, and the first major event to be held was an international rugby union match on 26 June 1999, when Wales beat South Africa in a friendly by 29–19, before a test crowd of 29,000. With total seating capacity of 74,500, it is the third largest stadium in the Six Nations Championship behind the Stade de France and Twickenham, which is the largest. It is also the second largest stadium in the world with a fully retractable roof, and was the second stadium in Europe to have this feature.