The little-known, 300-year history of the area includes former lives as a bustling tobacco port, parking lot, and industrial dump.

The 5.5-mile ring of steel posts around the Capitol Building is one of the largest (and most uniform) of its kind in the world.

The walls of the iconic dome are hollow and have a secret stairway.

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

This taxidermy horse was a Civil War hero.

For 60 years, the academy had no permanent location until members voted Washington D.C. as its forever home.

On the Fourth of July this area will transform into a Pompeii-like storm of falling embers and ash.

Those with a sharp eye can find the hidden image of a German Shepherd on the memorial's Mural Wall.

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

Peace Park and the Atomic Bomb Dome.

Part modern art project, part traditional chapel, this see-through church is only substantial from the right angle.

The glowing blue Nymphaeum of Emperor Tiberius.

The quintessential Japanese rock garden has existed for more than 500 years.

A monument to the two U.S. officers killed by North Korean troops while trying to trim a poplar tree.

The site of many tense prisoner exchanges across the Military Demarcation Line between North and South Korea.

The air force base preserves its scars from the Japanese attack on Pearl Harbor.

Once home to over 8,000 exiled Hawaiians suffering from Hansen's Disease.

A herd of 150 bison live on California's Santa Catalina Island and are at the heart of an ongoing debate between environmental protection and economic expansion.

An odd little fishing town that is inundated by tourists looking to be locked up in a cage and surrounded by great white sharks, because why not?

The oldest of its kind in the country, this tree sits where formerly enslaved people are said to have founded the city of Freetown.

No one is sure if the world's fourth-largest diamond had been found in a rubbish heap or was pawned by Napoleon's mom.

The legendary luxury train passage is commemorated with a charming museum inside its former eastern terminus.

Climb a steep hill in 90 seconds on the second-oldest urban subway in the world.

A gorgeous, Gaudí-esque stairway constructed in the city of Istanbul by a prominent Jewish family.