The Smithsonian Institution, an educational foundation chartered by Congress in 1846 and the world's largest research and museum complex, is responsible for maintaining most of the city's official museums and galleries. The U.S. government partially funds the Smithsonian, and its collections are open to the public free of charge. The Smithsonian's locations had a combined total of 30million visits in 2013. The most visited museum is the National Museum of Natural History on National Mall. Other Smithsonian Institution museums and galleries on the Mall include the National Air and Space Museum; the National Museum of African Art; the National Museum of American History; the National Museum of the American Indian; the Sackler and Freer galleries, which focus on Asian art and culture; the Hirshhorn Museum and Sculpture Garden; the Arts and Industries Building; the S. Dillon Ripley Center; and the Smithsonian Institution Building, which serves as the institution's headquarters.