A colorful architectural gem in Seattle's uniquely modern Central Library.

A little piece of the Shire is hidden behind a plant nursery in Port Orchard, Washington.

Couple's personal collection of pinball machines turned public pinball museum.

The world's oldest Jewish library was founded by Sephardic Jews in 17th century Amsterdam.

Three connected pink triangles memorialize persecuted gays and lesbians throughout history.

The attic of a four-century-old canal house hides a clandestine church.

The world's first zoo for microbes collecting the horrible and wonderful things living on and around us.

A small island abbey is the final resting place of many medieval Scottish monarchs, including the real Macbeth.

A 6th-century stone lies at the site of the mythical battle waged between King Arthur and his nemesis Mordred.

A network of concealed passageways lies within a busy London Underground station.

A toy store with a century-long history preserves the craftsmanship of playthings of the past.

This massive collection of British military artifacts includes the heartbreaking personal letters of the men in the trenches of WWI.

A collection dedicated to the treatment of disease, held in London's oldest hospital.

An alleyway plaque is all that remains of the independent Texas' envoy that forgot to pay their rent for over a century.

Catacombs turned marketplace.

The longest hedge maze in the world.

A special shop catering to the needs of things that go bump in the night, and also helps kids become writers.

Northern Ireland's Brobdingnagian stepping stones.

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

These fantastically named natural pools look like something out of a Scottish myth.

A kaleidoscopic warehouse-maze of handmade neon signs.

Tragic reminders of the 1945 firebombing campaign over Tokyo still haunt this bridge.

The romantic botanic tunnel feels like a well-kept secret.

The legendary cliffside castle of three-time Voivode of Wallachia, Vlad the Impaler.