Legend says this sacred tree was a gift from goddess Athena.

This amazingly preserved Gold Rush town is a historian's dream.

This historic iron-working village is now a ghost town so immaculate that it looks as though it was recently built.

A desert ghost town—occupied for only 12 years—was once home to more than 500 silver mines.

The ghostly remains of what was once the world's richest copper mine.

A mining town, now abandoned, was built in a canyon so narrow that the railroad ran right through the hotel lobby.

Standing in a state of "arrested decay," this ghost town allows for a detailed peek into Gold Rush life in an unusually harsh climate.

A giant Troll lurks under one of Seattle's oldest bridges.

One of the oldest active carousels in the country—but it might be missed by all but the keenest-eyed boardwalk strollers.

A remarkably opulent mansion with a tragic history.

Fake subway tiles were installed to cover a design that resembled the Confederate flag—it's unclear if the resemblance was intentional.

Designed as a labyrinth, this subterranean prison was crafted without bars or doors.

Iron Age runes and ruins hide in plain sight along this Portuguese beach.

Abandoned ships along a deserted beach feel like the set of a post-apocalyptic thriller.

The creek where a shark wreaked terror upon New Jersey, and served as the inspiration for "Jaws."

This ornate Victorian marketplace was the setting for Diagon Alley and the Leaky Cauldron in the Harry Potter films.

The Roman city was the birthplace of various emperors and is home to one of the empire's most impressive architectural feats.

Many of Edinburgh's more unsavory characters spent their final days behind this door while awaiting their executions.

This eerie abandoned building with a dark history is said to be one of the most haunted places in the Philippines.

This amazing 15th-century mural remained hidden in plain sight for centuries.

Inside this museum is an ongoing excavation of an ancient shipwreck.

A haunting collection of sunken wooden barges litters this Italian river bend.

A memorial to a larger-than-life legend, inside a county that also holds Bunyan's death certificate.

Inside this McDonald's you can dine on your Big Mac and fries next to a 2,500-year-old Roman wall.