The Hirshhorn Museum and Sculpture Garden is an art museum beside the National Mall, in Washington, D.C., the United States. The museum was initially endowed during the 1960s with the permanent art collection of Joseph H. Hirshhorn. It was designed by architect Gordon Bunshaft and is part of the Smithsonian Institution. It was conceived as the United States' museum of contemporary and modern art and currently focuses its collection-building and exhibition-planning mainly on the post–World War II period, with particular emphasis on art made during the last 50 years. Notable artists in the collection include: Pablo Picasso, Henri Matisse, Mary Cassatt, Thomas Eakins, Henry Moore, Jackson Pollock, Mark Rothko, Franz Kline, Hans Hofmann, Morris Louis, Kenneth Noland, John Chamberlain, Francis Bacon, Willem de Kooning, Milton Avery, Ellsworth Kelly, Louise Nevelson, Arshile Gorky, Edward Hopper, Larry Rivers, and Raphael Soyer among others. Outside the museum is a sculpture garden, featuring works by artists including Auguste Rodin, David Smith, Alexander Calder, Jeff Koons and others.