The National Gallery was designed, from its first day, to pick a fight with exclusivity. Founded in 1824 and opened at its current Trafalgar Square address in 1838, it was sited at the centre of London so the wealthy could arrive by carriage from the west while working Londoners walked in from the East End. Over 2,300 paintings, from Leonardo to Constable, free to anyone who showed up.

Look down in the entrance hall and you'll find something most visitors miss: floor mosaics by the Russian-born artist Boris Anrep, laid between 1928 and 1933, using the faces of Virginia Woolf, Greta Garbo and Winston Churchill as his classical muses. The building itself nearly looked very different. Prince Charles once called a proposed extension a "monstrous carbuncle on the face of a much-loved friend," and the design was scrapped.

VoiceMap's tours trace the gallery's wider London story, from the James Bond scene filmed in Room 34, where Daniel Craig's Bond broods over Turner's The Fighting Temeraire, to the Russian emigrant artist who left his muses' faces hidden in the floor.