We visited a lot of museums. One was the National Gallery, where they had a very good exhibit on Art Nouveau and even some Van Goghs. Amazingly, everyone was allowed to take pictures using a flash. A special film on the paintings is supposed to stop them from fading.

Another museum we visited was the Air and Space Museum (part of the Smithonean), where they have a lot of historic airplanes. The one below is the Spirit of St. Louis, which Charles Lindbergh flew across the ocean in the first solo crossing.

This Fokker (Dutch aircraft pioneer) was the first airplane to fly across the US non-stop.

They also have a lot of exhibits about the Space Program, such as this Lunar Lander...

and the space capsule used for the first American spacewalk.