The eternal city opens a vanguard center for contemporary art and architecture.

The ancient Romans may have invented the use of concrete for buildings—the Pantheon is still standing—but architect Zaha Hadid has perfected it. The fluid pale gray concrete curves of her boldly designed National Museum of XXI Century Arts, known by its Italian acronym, MAXXI, wind gracefully around a complex of restored military barracks in Rome’s Flaminio neighborhood. Inside, those sinuous surfaces create dramatic light-filled galleries, and multilevel atriums crisscrossed by painted-steel-enclosed stairs and cantilevered ramps lead visitors to two museums, one devoted to art, the other to architecture. The column-free spaces, capped by skylights atop ribbons of steel, maximize curatorial flexibility. (One of the temporary exhibition galleries is contained in a renovated factory.) Concrete has never been as permeable. Rome has never seemed so modern. MAXXI opens May 30 with five inaugural shows that focus on Italian contemporary artists, including a multimedia installation by Studio Azzuro titled “Geografie Italiane.”