Superstitious? Discover the witchy side of Mexico through its largest esoteric market.

An island filled with hundreds of hanging, decomposing, decapitated dolls.

This abandoned subway station beneath the Waldorf-Astoria hotel is allegedly used to secretly transport presidents.

This former Imperial summer home was the venue for a royal slap that once echoed 'round the world.

A sacred lake with thousands of sacred carp and a biblical history.

Hidden just under the waters around this Turkish island are the ruins of a once great city.

Memorials at a Florence railway station remember the citizens who were deported from Italy and sent to extermination camps.

This private skyway is filled with art and was expanded explicitly so that Hitler could appreciate a river.

This bronze boar's snout has been rubbed to a golden sheen by visitors seeking good fortune.

This museum is rotten with a century of wax medical deformities.

The doodles of a genius line the walls of a secret room under the Medici Chapel, where they were hidden for nearly 500 years.

The middle finger of modernity.

Go inside to really appreciate this 500-year-old technological masterpiece.

One of the most important yet well-hidden museums dedicated to the history of medicine.

An unremarkable wooden wheel built into the side of one of Rome's oldest hospitals was part of a policy to reduce infant exposure.

Architectural monsters are devouring this palace's every door and window.

The only "Egyptian" pyramid in Europe and the legendary tomb of Remus.

2300-year-old Roman road connecting the empire.

The yawning maw of this pagan visage is said to bite off the hands of liars.

Rome's semi-secret peephole vista is also a former Crusader stronghold.

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

Dress up like a miner and take a slide into the disco-lit depths of this once foundational salt mine.

Soaring over 6,000 feet in the Bavarian Alps, this beer garden was once Hitler's 50th birthday present.

This jaw-dropping 19th-century bridge uses its reflection to form what appears to be a perfect circle.