Guggenheim Museum Bilbao

Frank Gehry's spectacular museum of modern art, opened in 1997, with curving forms clad in shining titanium beside the river. It transformed Bilbao from an industrial port into a cultural destination. Outside, Jeff Koons's giant flower-covered dog, Puppy, guards the entrance, and Louise Bourgeois's huge spider Maman stands by the river.

Inside, see Richard Serra's huge steel sculptures and changing exhibitions. It's closed on Mondays outside summer. Bilbao's old town (Casco Viejo) has excellent pintxos bars.