The National Gallery of Art is an art museum on the National Mall in Washington, D.C. The museum was built in 1938 by the United States Congress. Andrew W. Mellon gave money and art to help the museum. Many lovers of art have given the National Gallery their art collections, like Lessing J. Rosenwald, Samuel H. Kress, and Joseph E. Widener. This has made the National Gallery one of the best art museums for Western art painting and sculpture in the world.