People escaping slavery may have hidden inside a corpse vault.

A diminutive memorial marks the site of a successful assassination by a right-wing death squad in America's capital.

Behind an abandoned storefront is an example of pioneering 1930s gas station architecture.

An overlooked tribute to one of the most important peace deals in American history.

A public art jibe at one of the United States’ oldest and longest-serving senators.

The oldest house in Washington, D.C. wasn't originally constructed in the nation's capital.

A hidden passageway now marks the site of an assassination attempt on Ronald Reagan that some say broke a 140-year-old curse.

The beautiful behemoth is one of the largest trees of its kind in the United States.

One incredible room in the Santa Barbara Courthouse is covered in wall-to-wall canvas murals.

This grisly effigy displays an early Christian martyr who was skinned alive and beheaded.

The secret medieval communication system will whisk your words above the noise of the crowd.

Five candy-colored villages on the Italian Riviera.

Brass cobblestones mark the places where individual Holocaust victims were taken from their homes.

All you ever needed or wanted to know about America's favorite whiskey, but not a drop to drink.

This railroad and oil tycoon's lavish estate now stands as a time capsule of the Gilded Age.

The alley connecting two of country music’s most historic venues has a rich history of its own.

This bar named after the world's first mixed cocktail was home to one of New Orleans' most notorious politicians.

The oldest standing structure in downtown San Diego.

One of the few remaining carousels built by master amusement park carver Charles I.D. Looff.

L. Frank Baum wrote part of the "Wizard of Oz" series in this wooden Victorian beach resort.

A sculpture of the famous photograph stands on San Diego's "Greatest Generation Walk."

The innocent intentions of this monument are somewhat lost in the sculpture's muscled imagery.

Visitors to this library are in for a real-world education in modernist architecture.

This little gem of Spanish Colonial architecture has been abandoned since the 1950s.