The National Library in Madrid (four million volumes), the Library of Catalonia in Barcelona (one million volumes), the university libraries of Santiago de Compostela (one million volumes), Salamanca (906,000 volumes), Barcelona (two million volumes), and Sevilla (777,000 volumes), Valladolid (500,000 volumes), and the public library in Toledo (with many imprints from the 15th to the 18th centuries) are among the most important collections. Spain also has 61 historical archives, among them the Archivo General de Indias in Sevilla, with 60,000 volumes and files, and the archives of Simancas, with 86,000 volumes and files. In total, Spain's public library collection holds more than 32.8 million volumes.
Spain has more than 600 museums. The Prado, in Madrid, with its extensive collection of Spanish art, is the most famous museum of Spain and one of the best in the world, featuring Picasso's world-famous Guernica . The National Archaeological Museum, also in Madrid, contains the prehistoric cave paintings of Altamira. The Museum of Modern Art, in Barcelona, houses excellent cubist and surrealist collections. There are also important art collections in the Escorial and Aranjuez palaces, near Madrid. Also in Madrid are the Museum of America, with artifacts from Spain's colonial holdings; the African Museum, with exhibits of many African cultures, especially Makonde art from Mozambique; and the Antiquities Collection of the Academy of History, founded in 1738, which houses Iberian and Visigoth artifacts, Islamic art, 4th century relics, including the Silver Dish of Theodosius, general European art, and 11th century documents. Barcelona also has the Museum of Ceramics, the Museum of Decorative Arts, a Picasso museum, the National Museum of Catalonian Art, and the Museum of Perfume. The Guggenheim Museum Bilbao, designed by American architect Frank Gehry, opened in 1997 as a joint project of the Guggenheim Foundation and the Basque regional government. The innovative design of the 24,000-sq-m (257,000 sq-ft) metal- and-stone structure has won worldwide attention and acclaim.