When it comes to vacationing in Washington, D.C., a family's best option is to start at the National Mall. Centered on or near the Mall are the 13 Smithsonian museums, galleries and gardens -- all free of charge -- including the Air and Space Museum, the Natural History Museum, the American Indian Museum and the African Art Museum. The National Zoo is just a short distance away.
When it comes to the National Mall and Memorial Parks proper, you've got a whole bunch of historical sites to tour. There's the Washington Monument, the Thomas Jefferson Memorial, the Lincoln Memorial and the Vietnam Veterans Memorial, to name a few. You can also tour a number of government buildings, including the White House.