The MDR-Sinfonieorchester is a German radio orchestra based in Leipzig. It is the radio orchestra of Mitteldeutscher Rundfunk, the public broadcaster for the German states of Thuringia, Saxony and Saxony-Anhalt. It is one of the oldest Radio orchestras in the world and the oldest in Germany. It was founded in Leipzig, Germany in 1923, with 115 musicians. Apart from a short interruption during World War II, it has been the main orchestra of the Central German Broadcasting Company since 1924. The orchestra performs concerts in Leipzig at the Gewandhaus.