Washington, D.C., is the capital of the United States of America. It is a planned city, designed specifically to house the federal government, and is not part of any state. Its history, beautiful architecture, and excellent cultural centers attract millions of visitors each year. Washington, D.C., is bordered by the states of Virginia and Maryland.
Before heading to D.C., research which events will coincide with your visit. Major international conferences, political events, or protests can hinder your sightseeing tour in dramatic fashion, and also send lodging prices through the roof. From Thanksgiving to New Year's is a much calmer time to visit, when the U.S. Congress takes its extended vacation. This means fewer official visitors, elected officials, and their staff members; transportation becomes less crowded and there are overall fewer people in the city.
If you are sightseeing, chances are you are on The Mall. The National Mall is a unique National Park, filled with an intense concentration of monuments, memorials, museums, and monumental government buildings instantly recognizable to people all over the world. The White House, the US Capitol Building, the Washington Monument, the Lincoln Memorial and Reflecting Pool, the Franklin Delano Roosevelt Memorial, the Vietnam War Memorial, the Jefferson Memorial, the National Gallery of Art, the Air and Space Museum, the National Natural History Museum, the Holocaust Museum, the International Spy Museum, the National Portrait Gallery—just a few of the top national attractions here, all within walking distance of each other. The tourist-designated sights are just half of the attraction here, though—to walk down the National Mall is to thread the halls of world power in the modern era. Here the world's most powerful politicians and their staffs fill the grand neo-classical buildings of the three branches of US Government, where they make decisions every day that reverberate in the remotest corners of the world.
The Washington Zoo is an excellent zoo which is an informative and free day out. Be prepared to walk if you wish to cover the whole zoo, it's said to be up to 10 miles. The staff are enthusiastic and always willing to help. Easily accessed from the subway, 500m walk from the closest stop (Woodley Park-Zoo). Be sure to pay a visit to Tai Shan the Giant Panda.