Tate Modern

Converted from the shell of a disused riverside power station in 2002, Tate Modern exhibits our national collection of modern and contemporary art dating from 1900. Yet it is also far more than that. Free to enter, and open late at nights at the weekend, it's become a centrepiece of London's thriving cultural life. It does get busy, but the building is enormous and the temporary exhibitions are often world class. A good way to start would be to head for two of my favourite rooms - starting with number 7 on Level 3, which has work by Monet, Rothko and Pollock. Then go up to number 3 on Level 5, which is filled with intriguing sculptures, mostly from the late 1960s. On the way you will almost certainly get distracted, and so it should be.