This modest marker near Notre Dame identifies the very center of Paris.

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

The ruins of the largest gladiatorial school in Rome are largely hidden under modern streets.

The home of one of America's most wealthy industrialists is now a historic site that remembers a more decadent time in the country's history.

The real-life site of Ichabod Crane's infamous gourd attack.

This "second" cemetery represents New Orleans' attempt to keep cholera at bay.

Parts of the civil rights movement unfolded in this historic eatery, helmed by the "Queen of Creole Cuisine."

A remnant from the golden age of aviation still in use today, Pan Am's Clipper service took off from this Art Deco gem.

This crumbling industrial fortress has attracted daredevils, filmmakers, and historians.

This sculpture of a fisherman spent six years at the bottom of the Schuylkill River.

A heartbreaking monument showing the last morning in the life of Jane Griffith.

Europe’s most powerful hot spring supplies the surrounding region with hot water.

A free, canine-friendly alternative watering hole near the more famous Barton Springs.

This massive oak tree has ties to the first native tribes of the region and the founders of Texas.

Home to an endangered salamander, a full moon celebration, and a large spring-fed outdoor swimming pool.

This statue is the only female representation of Rome's "talking statues."

A mysterious chasm in the heart of the ancient Roman Forum, the Lacus Curtius was once believed to be a gateway to hell.

In the early Roman Empire, people deemed traitors and criminals were tossed to their deaths from this rock.

Legend has it that this bronze orb, which sat atop an ancient Egyptian obelisk, once held the ashes of Julius Caesar.

New York's unstoppable progress turned this cemetery into the smallest burial ground in the city.

Named the fifth most beautiful building in America in 1885, this former courthouse boasts the best view in the Village.

The oldest operating apothecary in the US has treated everyone from Thomas Edison to Mark Twain.

Jimi Hendrix's legendary recording studio in Greenwich Village.

This Italian stadium makes liberal use of fascist statuary to evoke classical sporting arenas.