One of Canada's most incredible rare book collections holds hundreds of thousands of gorgeous tomes that the general public can touch.

A 98-room castle in the middle of Toronto that bankrupted a 19th century electricity multimillionaire.

A botanically themed auditorium blooms within the world’s last operating double-decker theater.

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

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

The intricate stonework of Machu Picchu serves as a testament to Incan engineers.

Frank Lloyd Wright’s most iconic home dangles over a Pennsylvania waterfall.

The world's longest known cave system.

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

Explore the largest pure gypsum deposit in the world, and go dune sledding while you're at it.

Elevated freight railway turned wildly successful urban park.

The perfectly preserved underground rooms where Churchill plotted the war against Germany.

Kings Cross Station pays tribute to its role in Britain's best-selling book series.

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

London's creepiest cemetery was once the site of dueling magicians and mobs of stake-carrying vampire hunters.