Corn-inthian columns with a uniquely American take on neoclassical architecture.

Part of a WWII submarine is lurking outside the Washington Navy Yard parking lot.

The first memorial dedicated solely to the Black troops who fought for the Union.

A secret greenspace hides atop a Capitol parking garage.

This statue of one of baseball’s greatest pitchers looks like something out of a sci-fi horror movie.

This Delaware River bridge is emblazoned with a catty slogan from a more prosperous time.

Frank Lloyd Wright built this suburban synagogue late in life, but it stands among his most iconic masterpieces.

Why have you never heard of the second most popular tourist site in New York?

Collapsing castle on the Hudson river was once the storage site of military surplus business.

This Yellowstone geyser may not shoot as high as the nearby Old Faithful, but it erupts for considerably longer.

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

This private residence was the template for one of the most beloved television homes of all time.

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

The spot in the Mile-High City that's exactly 5,280 feet above sea level (at least for now).

This former coal gasification plant found a curious second life as a popular public park.

Portlandia is the second-largest copper repoussé statue in the United States.

This extravagant Art Nouveau rest stop features a million-dollar view of the Columbia River.

The wooden airship was the largest flying boat ever built.

Home to the deepest rift anywhere on Earth.

The world's first nuclear power plant is open to visitors looking to role-play a meltdown.

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

An apocalyptic seismic event creates a deadly chain reaction that ends with a 6-mile long lake developing within weeks.

An architect's childhood fantasy treehouse made real.

One of nature's most well-scheduled phenomenons resides in Wyoming's Yellowstone National Park.