While many places make the claim, the Library of Congress says this restaurant is the birthplace of the hamburger.

CDMX's home for the world's culinary delights.

Once home to an aristocratic family and a workers' organization, this intricately tiled building now houses a chain restaurant.

Cool down and fill up after visiting Teotihuacán at this bar and restaurant in a deep, underground cave.

Known as the site of 'El Dorado,' this mysterious lake is rumored to hold gold beneath its waters.

Thomas Edison's home and final resting place also boasts an impressive garage, where some of the earliest electric cars are on display.

Take a step into the workshop where Edison and his employees revolutionized the world.

A playground inspired by differential calculus dangles from the ceiling of the Liberty Science Center.

Touching this little fossil embedded in the wall of a grand mosque-cathedral may make your wishes come true.

A curious carving hides on a marble column in the Mosque-Cathedral of Córdoba.

Spain's unique Mosque-Cathedral has been a place of worship for both Muslims and Christians throughout its history.

Seven early Christians were sealed into a cave where legend has it they slept unharmed for centuries.

Twice a day a speeding train passes only inches from the homes of this residential neighborhood.

A fortress on this island housed the mysterious prisoner known as the "Man in the Iron Mask" for more than a decade.

The celebrated eyesore created by starry-eyed sweethearts.

The tradition of open-air secondhand and antiquarian bookselling in Paris dates back to the Renaissance.

The first green space constructed on an elevated viaduct.

The very center of Paris is surrounded by a bevy of strange good luck rituals.

The gorgeous entrances into the city's underbelly look more like grand halls than subway stops.

This influential Renaissance-era library was once the haunt of kings and monks.

Ancient snack bar of the Roman Empire re-opened.

“Invented in Key West, Perfected in Brooklyn."

Over 20,000 sets of spice shakers reveal the surprisingly telling history of our most basic spices.

The oldest family-run restaurant in the United States is a living museum of New Orleans dining history.