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Photo: via Wikimedia Commons, Public domain
The plantation house of Robert E. Lee and his ancestors. Guided tours are available and the grounds have great views looking down into Washington, D.C.
Arlington House is the historic Custis family mansion built by George Washington Parke Custis from 1803 to 1818 as a memorial to George Washington. Currently maintained by the National Park Service, it is located in the U.S. Army's Arlington National Cemetery in Arlington County, Virginia. Arlington House is a Greek Revival style mansion designed by the English architect George Hadfield. The Custis grave sites, garden and slave quarters are also preserved on the former Arlington estate.
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Final resting place of President John F. Kennedy and many other members of the Kennedy family
The memorial honors the contribution of women to America's military. In 1932, McKim, Mead and White designed a gateway to Arlington Cemetery, and in 1997 a mostly underground museum opened behind that historic structure. It features informational displays and historic artifacts and uniforms. A national parks passport stamp is available at the gift shop's checkout.
Just as the name says, this tomb sited on a picturesque hill overlooking Washington, D.C., is the resting place of one soldier each from World War I, World War II, and the Korean War whose bodies could not be identified. (Due to advances in DNA testing, a soldier from the Vietnam War formerly entombed here was identified and reinterred, and it's likely that there will be no more unidentified soldiers from now on.) Guards in pristine dress uniforms maintain a 24/7 patrol in a meticulous back-and-forth pattern: 21 steps, turn and shoulder arms, pause for 21 seconds, and repeat. Even inclement weather does not stop them (although there is a shelter used very occasionally in extreme conditions). The prestigious post is not entirely ceremonial; the guards are armed and will interrupt their routine to silence loud or disrespectful visitors or stop anyone (including children and tourists with cameras) who approaches too close. A formal Changing of the Guard ceremony is held half-hourly in summer and hourly in winter. The solemn ceremony is a popular sight to watch, but if you want to spend some time in quiet contemplation you may find the crowd and their cameras disruptive; instead, aim to arrive just after the ceremony when the crowd thins out until the next one.
Contains information about the cemetery and the tomb of the unknown solder. There is also a large parking garage which can be a good place to dump your car before catching the subway into D.C.
A private tour company which provides hop on/off tram to get around the cemetery provides a way to explore the entire cemetery (which is enormous and hilly) in a short amount of time.
A symbol of freedom and friendship between the Netherlands and the U.S. since World War II.