Hidden beneath the streets of London is a secret subway that only carried mail.

An eerie, derelict amusement park in Berlin.

The sign at the garden gate reads: "These Plants Can Kill."

On the Oregon coast there is a natural hole that seems to be draining the sea.

World's largest collection of serial killer artwork and other macabre exhibits.

The mysterious, fantastical woodland inspiration for "The Lord of the Rings."

On Japan's Tashirojima Island, cats are king.

A huge musical instrument played by the ocean.

During prohibition, corrupt city officials ran drinking dens under the streets of Downtown Los Angeles.

Once adorning a New York skyscraper, these reclaimed ruins now haunt an Indiana park.

This shop is named for a runaway elephant who smashed through its doors, stole some peanuts, and spent five days on the lam.

A medical facility that has been kept frozen in time.

Pennsylvania's highest point is spotted with boulders which were pushed to the surface by nothing but cold.

The largest open-air contemporary art center in Latin America is a unique experience in the Atlantic Forest.

Mirrored floors and arched shelves create the illusion of an infinite tunnel of books.

An ever-growing literary collection housed in the apartment where the Russian author penned his final novel.

The small family-run business has kept alive the fading art of creating beautiful handmade book covers.

At the United Kingdom's only residential library you can sleep among the books.

Tile mosaics and quotes from Pablo Picasso add an artistic flair to these bus stop benches.

A magical museum of fairy tale treasures near Cyprus' buffer zone.

A whimsical village of unique treehouses resides in a Washington forest.

A flamboyantly decorated bridge signals diversity and fellowship at the entry to Indianapolis' Broad Ripple Village.

A 30-year-old Sycamore tree grown from a seed taken to the moon and back.

The history of the treatment of mental illness, illustrated in all its gory detail, and housed in an asylum.