A line of blue paint marks the route of the inaugural parade.

Soldiers were buried next to Lee's house in the center of Arlington Cemetery to dissuade the general from reclaiming his property after the war.

The controversial urban planner who designed Washington, D.C., was buried in Maryland, and can presently be found in Virginia.

This isn't your average roadway—it's actually a National Park and a transportation pioneer.

This colonial tavern played host to George Washington, Thomas Jefferson, and other famous early Americans.

A former major munitions plant that has been converted into a sprawling art space.

One of the most influential presidents in U.S. history wanted only this plain, elegant monument as his lasting memorial.

A three-story tower of books about Abraham Lincoln is one of the more unusual monuments to the president.

Architecture lovers won’t stop touching the National Gallery's 19.5 degree marble prow.

"Congress may voluntarily remain in session throughout the summer, in order that our Congressmen may be protected from the intolerable discomforts and dangers of the ordinary outdoor weather!”

Washington's iconic carousel has a nice piece of Civil Rights history.

Go take a picture with the inventor of the daguerreotype photographic process.

This stunning blue and gold room changed cities twice before becoming part of the Smithsonian.

A much-maligned monument to teetotalism.

Light bulbs, scrap wood, and tinfoil comprise this homemade throne of the gods.

There’s a hidden military meme engraved on the World War II Memorial.

The actual model from the original "Star Trek" series is now on display at the National Air and Space Museum.

The most decorated dog of World War I is preserved in the Smithsonian.

During the Industrial Revolution this “Temple of Invention” was full of intricate miniature machines and gadgets.

A hidden gem on the lawn of the U.S. Capitol Building designed by landscape architect Frederick Law Olmsted.

A tiny piece of the Moon is embedded in this stained glass masterpiece.

A legal loophole makes it possible to get away with murder within this 50-square-mile section of Yellowstone.

This rustic old building is said to be the most photographed barn in America.

Giant, natural amphitheaters made of delicate geological formations called "hoodoos."