The Singapore Indoor Stadium is an air-conditioned, multi-purpose pillarless arena in Kallang. Designed by the Japanese architect Kenzo Tange and officially declared open by Singapore's first Prime Minister, Lee Kuan Yew, in 1989, it sits beside the National Stadium as part of the Singapore Sports Hub. Its flexible configuration accommodates from 4,000 to 12,000 spectators depending on the event. It has hosted international concerts, family entertainment, award shows and a wide range of indoor sports including badminton, basketball, netball and mixed martial arts.