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

A Lovecraftian altar of nightmarish bronze chairs sits ominously on a boardwalk in Puerto Vallarta.

World's largest cave was only discovered in 1991, and now offers tours to the public.

A massive underwater sinkhole made famous by Jacques Cousteau.

The second-deepest known cave on Earth, hidden in an extremely remote mountain region.

The gorgeous library at Trinity College is home to remarkable treasures of Irish identity.

This shell of a historic manor house on the Isle of Wight is said to be the most haunted site on the island.

This famous city eluded concrete detection until the early 2000's.

This domed temple was built in a hidden cave mouth as a refuge for sinners seeking absolution.

Bright, rebellious indigenous murals dating back to the Spanish Conquest inexplicably cover the walls of this Catholic church.

This historic general store still operates much as it did in the late 1800s.

Deadliest lake in the world suffocated over 1,746 people in one night.

A swing to dangle you off the very edge.

A waterfall 600 ft. inside a mountain, once the bane of gold miners, is now a spectacle of nature.

The "Prussian Versailles" that is as glorious today as when it was built.

This angular Dwarven tunnel cuts through a mountainside in Glacier National Park.

Gambling, boozing, and yodeling animals cover the walls of this dive bar cum natural history museum.

The sound of swaying stalks in this stunning grove has been named a governmentally recognized sound.

San Francisco's newly reopened hands-on science museum.

Every inch of this chapel is covered in craftsmanship from across the world.

A charming flea market shop dedicated to retrofuturistic apparati.

This incredible stone temple is a monument to death, victory, and fantasy architecture.

A movable feast that is an East London institution.

The secret city built by the Manhattan Project.