The Musée d'Art Moderne is the city's own collection of twentieth-century art, in a wing of a building put up for the world's fair of 1937. Two long wings of pale stone face the river, with a colonnade along them and an open terrace between. Nothing here was updated to another decade: the stripped columns and the sculpture on the river front are 1937 through and through. You arrive across that terrace, which is where the fair crowds arrived too, and go in from there.
One room here was built for a single painting. Raoul Dufy's La Fée Électricité runs round a curved wall in 250 panels and covers about six hundred square metres, which makes it one of the largest paintings ever made in France. The electricity company commissioned it for the fair, and it shows a hundred and ten scientists and thinkers who had a hand in electricity, with gods above them. Two versions of a Matisse mural hang here as well, including the one he had to paint again because the wall measurements turned out to be wrong. In 2010 a man cut five paintings from their frames overnight, and none has been recovered.