It’s about a 3-block walk—and a much larger aesthetic leap—from the Prado to the Reina Sofia, which holds Spain’s most significant collection of 20th- and 21st-century works. In fact, that collection has swelled so extensively in recent years that it now uses the two 19th-century exhibition palaces in the Parque del Retiro as spaces for temporary shows (often installation art) that require large physical spaces. The main museum consists of the neoclassical 18th-century former General Hospital designed by Francisco Sabatini, and the post-modern non-rectilinear addition by Jean Nouvel that opened in 2002.

Every few years the Reina Sofía curators rethink how to present the permanent collection. It is hung in rough chronological order but with various “movements” grouped by room. The movements and their accompanying wall texts change, even when the art remains the same. For the time being, two floors of the Sabatini building contain “permanent” chronological exhibits: “The Irruption of the 20th Century: Utopias and Conflicts (1900–1945)” fills Level 2 (Guernica is in Gallery 206); and “Is the War Over? Art in a Divided World (1945–1968)” occupies Level 4. The missing chronological gap is found on Level 1 of the Nouvel building, where “From Revolt to Postmodernity (1962–1982)” covers art as it lost its boundaries with pop culture, and includes a lot of work by American pop artists, just as the 1945 to 1968 galleries have several Abstract Expressionist works, also by Americans.

Current pedagogy declares that in modern art, context is everything because the horrors of the 20th century invalidated old Platonic concepts of art as a reflection of eternal beauty. Abstractions aside, that means that paintings by Picasso, Juan Gris, Joan Miró, and Dalí are surrounded by photographs, posters, advertising art, and short films that provide context for the world in which the art was created. This approach is particularly effective in the galleries that deal with art related to the Spanish Civil War, including Guernica. Picasso’s response to the unprovoked bombing of a small Basque village remains one of the most powerful antiwar statements ever made.

The sculpture-filled courtyard of the Sabatini building is open during warm weather for light snacks. (Contrary to expectation, the coffee cart, which also sells wine and beer, is not a performance installation.) Admission to blockbuster temporary exhibitions is usually through the Sabatini entrance. Those interested only in the permanent collection enter through the courtyard of the Nouvel building. Pay attention to signage or you could wait an hour or more in the wrong line. Having a Paseo del Arte pass, Madrid Card, or advance online purchase provides priority admission.