Behind its incongruous white-stucco facade, at No. 12 Carlton House Terrace, the ICA has provided a stage for the avant-garde in performance, theater, dance, visual art, and music since it was established in 1947. There are two cinemas; a library of video artists' works; a bookshop; a café; a lively, hip bar; and a team of adventurous curators. COST: 1-day, weekday membership £1.50; weekends, £2.50; additional charge for cinema screenings. Tube: Charing Cross or Piccadilly Circus.