Baker Street is a street in the Marylebone district of the City of Westminster in London. It is named after builder William Baker, who laid out the street in the 18th century. The street is most famous for its connection to the fictional detective Sherlock Holmes, who lived at a fictional 221B Baker Street address on the north of the street, the ballad song "Baker Street Muse" by Jethro Tull from their 1975 "Minstrel in the Gallery" album, and also for the 1978 pop hit by Gerry Rafferty of the same name Baker Street. The area was originally high class residential, but now is mainly occupied by commercial premises.