Arlington National Cemetery

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.

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.

Final resting place of President John F. Kennedy and many other members of the Kennedy family

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.

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.

Compelling memorial that commemorates the amphibious landing and eventually victorious battle for the Pacific island of Iwo Jima during World War II. If you walk around the memorial counter clockwise, you'll notice the optical illusion of the marines planting the flag. On July 4th, this spot also provides an excellent view of the fireworks.

While lingering is not recommended for security reasons, you should know it is the largest office building in the world, and covers 4 zip codes. (Army, Navy, Air Force and Department of Defense). Tours are available by online reservation made 14-90 days in advance. The Pentagon Memorial is open 24 hours to visitors on the Washington Blvd side, where Flight 77 hit. Photography is allowed at the memorial, but is not permitted anywhere else on the Pentagon grounds— take photos anywhere else on site, and you may face a lengthy interrogation by the Pentagon Police and will probably be asked to delete the images. On a lighter note, the interior courtyard is irreverently referred to by employees as "Ground Zero," as it was the target of a number of Soviet missiles during the Cold War. There is no public parking at the Pentagon but it is about a 5-minute walk from the Pentagon City Mall through a tunnel.