 A gradual rebuilding, using construction materials from the ruins of the MKK, began in the late 1940s.The first exhibition at the Museum am Ostwall was held in 1949 – making it one of Germany's first post-war museums of 20th-century art – and it continued to be expanded until 1956.The MKK, meanwhile, was provisionally rehomed in Cappenberg Castle until its return to Dortmund in 1983.