One of the greatest collections of European art in the world, dating from 1250 to 1900, are exhibited at the National Gallery of London. This means that it covers paintings from the Italian Renaissance to the French Impressionism including Raphael, Monticelli, Seurat, Goya, Cezanne, Monet, Renoir, Van Gogh and Picasso, as well as world ethnic art and sculptures. The whole art world is in there.
But what is really amazing is that there is no entrance fee.
Art lover or not, it is a must. But do expect the crowds.