The National Gallery of Art is to be found in the National Mall on Constitution Avenue. In the collection galleries and sculpture garden, there are American and European paintings, photographs, sculptures, and decorative arts. Arguably the best collection is the Italian Renaissance collection, which includes the only Leonardo da Vinci painting in the Americas. The West and East buildings are connected via underground tunnel.
When people refer to the National Mall, they are normally talking about the area that includes the Lincoln Memorial, the Washington Monument, and the United States Capitol. The entire National Mall area is a great place to receive the symbolic, monumental feeling that so many seek in visiting to Washington D.C. The Mall is maintained by the National Park Service.
This is the place to go if you want to experience the complete historical collection of aircraft and spacecraft! The museum is also known for its explorations of planetary science and terrestrial geology and geophysics. Some of the many impressive exhibits include Chicago, the first aircraft to fly around the world, Apollo 11 command module, Soviet SS-20 and US Pershing II Rockets, Ballistic Missiles, and the space suit worn by David Scott on Apollo 15.
This Center for the Arts sits on the lovely shores of the Potomac River and is more commonly referred to as the Kennedy Center. Every year the center hosts about 2,000 shows, making it the most active Center for the Arts in the country. The center boasts shows of dance, theater, folk music, jazz, orchestral, chamber, and popular varieties. With this many choices, you're sure to find what you're looking for!
The National Zoo's official name is actually the National Zoological Park, so don't get confused if you hear this title instead! This completely free institution has two "campuses," a 163-acre urban park for your wandering type, and the other a 2,300-acre area called the Smithsonian Conservation Biology Institute. The park indeed takes conservation seriously: 1/5 of the animals in both locations are endangered or threatened. So, not only do you not have to pay, but you're able to witness some of the rarest animals on earth, such as giant pandas, and learn about why they are threatened in the wild and what you can do about it.