Bowie moved to Switzerland in the second half of 1976. There, he began exploring other art forms and visiting galleries in Geneva and the Brücke Museum in Berlin, becoming (in the words of biographer Christopher Sandford) "a prolific producer and collector of contemporary art ... Not only did he become a well-known patron of expressionist art, locked in Clos des Mésanges he began an intensive self-improvement course in classical music and literature, and started work on an autobiography." Later that year, Bowie, along with friend and singer Iggy Pop (who had accompanied Bowie on the Station to Station Tour), retreated to Berlin in a further attempt to escape his addiction and the spotlight: