This mysterious structure by the Washington Monument is a flood barrier designed to protect the White House against rising waters.

Decades before the scandal, this staircase on the river was a literal "water gate."

A monument in Washington D.C. marks the spot from which all other roads were supposed to stem.

The beloved statue at the National Academy of Sciences is oh so inviting to sit on.

The first purpose-built art gallery in the United States is once again open as a center of craft arts.

The site of the climactic scene from the classic horror film is now a historic landmark.

This seemingly out-of-place gas station by the Watergate hotel was once described as the most expensive gas station in the world.

A historic arena where the Beatles played their first concert in the U.S.

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

The sci-fi villain is a little-known inhabitant of the U.S. capital's largest cathedral.

A girls' boarding school inspired by the Chicago World's Fair, once abandoned, now restored to strange and scenic glory.

The tallest The Church of Jesus Christ of Latter-day Saints temple in the world soars above the Beltway.

A benevolent, 16-foot-tall river dragon lives on a suburban lawn.

Giant acorn-shaped 19th century gazebo from which suburban Washingtonians gazed upon the original "silver" spring.

Long hidden under grime, the politically radical murals of a little known Yugoslavian master are finally getting their due.

An 18th-century Catholic church converted into an eccentric temple of music and bacchanalia.

A portion of the old Pirates stadium over which a defining home run once flew still stands even after the rest of the stadium was torn down.

A take-out restaurant that only serves cuisine from countries with which the United States is in conflict.

The largest university building in the West is a gothic masterpiece containing dozens of theme rooms based on different countries.

A model of a dinosaur that was named for Andrew Carnegie stands outside the museum that also bears his name.

Meet your friends, marry your true love, or tell your enemies to kiss your butt under this historic Pittsburgh timepiece.

The United States’s oldest funicular railway glides up and down a steep Pittsburgh street.

The only way to see Pittsburgh is from the top of this lookout point, just like the ancient members of the native peoples did.

One of the steepest streets in the United States makes an intriguing challenge for cyclists.