Museo Nacional del Prado

After more than a decade of planning and construction, and an outlay of $210 million, Spain's most revered cultural icon unveiled its 237,000-square-foot expansion in 2007, designed by Rafael Moneo. Once the purview of Spanish kings, who bought directly from Titian, Velázquez, Rubens, and Goya, the Prado has a collection long ranked among the world's finest. Moneo's extension adds galleries, an auditorium, restaurants, and a bookstore, and also embraces another Madrid landmark, the 17th-century cloister of the Jerónimo Church. Prado director Miguel Zugaza, who has overseen the trans_formation, notes enthusiastically: "It's time for Spain's principal cultural institution to face the future—and we're ready."