This ex-power station was built in the 1930s, and after a dazzling renovation by Herzog & de Meuron, provides a magnificent space for a massive collection of international modern art. The vast Turbine Hall is a dramatic entrance point to the museum. On permanent display in the galleries are classic works from 1900 to the present day, by Matisse, Picasso, Dalí, Moore, Bacon, Warhol, and the most-talked-about British upstarts. The works are not grouped by artist but are arranged in themes that mix the historic with the contemporary -- Landscape, Still Life, and the Nude -- on different levels, reached by a moving staircase, which is a feature in itself. You could spend a visit merely exploring one floor, but that would be cowardly, as there's usually one major barnstorming exhibition to see (for which there is a charge, and often very long lines waiting to get in), which is always the talking point of Londoners who have their fingers on the pulse. COST: Free. Tube: Blackfriars or Southwark.