Thialf is an ice arena in Heerenveen, Netherlands. The stadium is used for long track speed skating, short track speed skating, ice hockey, figure skating, and non-sports events. The outdoor rink was opened in 1967, and the indoor stadium was opened in 1986. Several world records were set in the indoor stadium. Annually, Thialf hosts two Speed Skating World Cup events. The arena has a capacity of 12,500 seats. The street it is located on is named after Dutch bandy pioneer, Pim Mulier.