Museo Reina Sofía

Spain's national museum of 20th-century art, built around a single overwhelming reason to visit: Picasso's Guernica, displayed in its own room exactly as the artist intended. The permanent collection beyond it covers Dalí, Miró, and the full arc of Spanish modernism.

Guernica draws the crowds, but the museum's Miró and Dalí rooms on the same floor are just as worth the time and considerably calmer. Free entry applies Monday, Wednesday–Saturday 19:00–21:00 and Sundays 13:30–19:00 — arrive right as it opens for the smallest queue. The glass exterior lifts, added during Jean Nouvel's 2005 extension, are themselves a small architectural attraction, framing views back across the Atocha rooftops.