The National Air and Space Museum is a Smithsonian Institution museum located in Washington, D.C., United States. It holds the largest collection of historic aircraft and spacecraft in the world. Its main building is located near the National Mall and the Smithsonian Institution. The museum houses many important collections such as the Spirit of St. Louis, the Apollo 11 command module, the Wright brothers' plane and Charles Lindbergh's transatlantic flight.

The museum was established in 1946 and is divided into two main buildings: the new Steven F. Udvar-Hazy Center in Chantilly, Va., and the original building on the National Mall in Washington, D.C. The National Air and Space Museum has been visited by more than 300 million people since it opened in 1976 and is the most visited museum in the world.

The museum has a collection of more than 60,000 objects, including aircraft, spacecraft, missiles, rockets, astronomical and scientific instruments, and other space-related artifacts. The National Air and Space Museum also has a number of educational programs and activities for visitors. The museum offers interactive exhibits, educational programs, and live demonstrations. The museum also hosts lectures and symposiums on a variety of topics related to air and space exploration.