Hamburger Kunsthalle

Most people come to the Hamburger Kunsthalle for one figure: a man in a green coat standing on a rocky peak, his back to us, looking out over a sea of drifting fog. Caspar David Friedrich painted this 'Wanderer above the Sea of Fog' around 1818, and it has become the defining image of German Romanticism, reproduced on more book covers than almost any other painting.

The museum around it opened in 1869, a grand civic gallery built by the merchants of this trading city, and it has kept collecting ever since across three linked buildings, including a cube of pale stone added in the 1990s for modern art.

The Friedrich is the anchor of a deep 19th-century collection, and the picture itself only reached Hamburg in 1970. The rooms carry you on to Manet and the German Impressionist Max Liebermann, then into Klee, Kirchner and the 20th century. But it is that lone traveller on the crag, turned away from every visitor who stops in front of him, that the crowds photograph.