LONDON (AP)— It's the disused power station that became an art-world powerhouse, and now London's Tate Modern is even bigger, with a new 10-story wing to help absorb more than 5 million visitors a year.

The gallery beside the River Thames opened in 2000 and succeeded beyond its creators' wildest dreams, becoming the world's most visited modern art museum.

This week it opens a 260 million pound ($367 million) pyramid-shaped extension by Swiss architecture firm Herzog  & de Meuron.

The gallery now has 60 percent more space, more works by women and a more international focus to the collection.

Tate director Nicholas Serota said Tuesday that the gallery now shows ``a much more diverse range of work'' – and offers visitors ``a new view of London'' from a terrace atop the pyramid.