Tate Modern

Thanks to its industrial architecture, this powerhouse of modern art is awe-inspiring even before you enter. Built after World War II as Bankside Power Station, it was designed by Sir Giles Gilbert Scott, architect of Battersea Power Station. The power station shut in 1981; nearly 20 years later, it opened as an art museum, and has enjoyed spectacular popularity ever since. The gallery attracts five million visitors a year to a building intended for half that number; the first fruits of work on the immensely ambitious, £215m TM2 extension opened in 2012: the Tanks, so-called because they occupy vast, subterranean former oil tanks, will stage performance and film art. As for the rest of the extension, a huge new origami structure, designed by Herzog & de Meuron (who were behind the original conversion), will gradually unfold above the Tanks until perhaps 2016, but the work won’t interrupt normal service in the main galleries.

In the main galleries themselves, the original cavernous turbine hall is still used to jaw-dropping effect as the home of large-scale, temporary installations. Beyond, the permanent collection draws from the Tate’s collections of modern art (international works from 1900) and features heavy hitters such as Matisse, Rothko and Beuys – a genuinely world-class collection, expertly curated. There are vertiginous views down inside the building from outside the galleries, which group artworks according to movement (Surrealism, Minimalism, Post-war abstraction) rather than by theme.