National Air and Space Museum

The Smithsonian's aviation and space museum on the south side of the Mall, for decades the most visited museum in the world and still among the top few. Highlights include the Wright Flyer of 1903, Lindbergh's Spirit of St. Louis, the Apollo 11 command module Columbia, a lunar sample you can touch, the Bell X-1 that broke the sound barrier and a Wright-era to Space Shuttle-era sweep of hardware. A multi-year renovation completed in phases through 2026 has rebuilt all galleries.

Practical: Free, but timed-entry passes are required and should be booked online in advance, as they run out on summer days. Allow two hours. The much larger Udvar-Hazy Center annex near Dulles Airport houses the Space Shuttle Discovery, an SR-71 Blackbird and the Enola Gay, and is a logical last stop before a flight home.