The beautiful tunnel that ran from the lobby to Penn Station is still hidden underneath 34th Street.

This expansive bridge in the Canadian wilderness was originally just built for friends.

Mysterious 500-year-old tapestries depict a unicorn hunt.

This cemetery has graves dating back to the 17th century, including the city's oldest carved tombstone and an ominous cryptogram.

An ancient capital city that dates back 3,000 years old and harbors many surprises.

A walk-in working camera obscura produces 360-degree live images of the San Francisco coast.

Macabre astrological automaton clock dating to the late 1400s.

This natural wonder drops 16 stories straight down through rare flora and streaming waterfalls.

Staves, storm-calling, and of course, necropants.

This London pub hides a peculiar secret: a recreation of the rooms shared at 221b Baker Street by Sherlock Holmes and Dr. Watson.

360° views of the city plus five floors of optical illusions and hands-on science.

Famously misunderstood wonder of the ancient world

A library of rare occult books in Los Angeles.

This little museum is built on a theater that was once a wildly elaborate speakeasy.

The world's largest collection of witchcraft regalia.

Two thousand artifacts from around the world collected by one woman who loved to travel.

A museum of carnival attractions where you are invited to ride the rides.

Under a glass sidewalk lie the remains of some of Manhattan's oldest buildings.

A charming 17th-century alley is lined with secondhand bookstores and antiquarian shops.

Franciscan monks created a facsimile of the Holy Land for North Americans who couldn’t afford the trip overseas.

A hands-on traveling collection of the innovative devices of yesteryear.

This South London cemetery holds the remains of more than 15,000 people.

Stepping away from the glitz of mobsters and casinos to learn about the other history of Vegas.

This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.