The world of the ancient Celtic civilization explained through a bewitching 11 acre garden.

A moody and picturesque riverside ruin overgrown with vegetation.

A submerged archeological park still holds the wonders of a Roman Sodom.

A local tree surgeon has created a whimsical walk full of carved tree stumps near Scotland's Loch Lomond.

Hidden behind a wall for decades, this masonic lodge was only rediscovered during renovations.

While these wooden totems bear a striking resemblance to First Nations artwork of British Columbia, their actual origins lay on the opposite side of the Pacific Ocean.

A faux desert landscape in the middle of the jungle that sprouts oases during the rainy season.

A battle between nature and architecture in the Cambodian jungle.

The abandoned ruins of a beautiful medieval castle just outside Barcelona.

The shockingly unspoiled Peruvian tomb of the Lord of Sipan was once guarded by a footless warrior.

Rich with fauna and flora, nature-lovers can walk across the sea at this UNESCO World Heritage spot.

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

Europe's second largest ossuary wasn't discovered until 2001.

A cheeky architectural easter egg.

Mummified monks and the accidentally interred, in a 17th-century crypt.

A 1,215-foot tunnel transports pedestrians beneath the River Thames.

A Victorian natural history and ethnographic museum with wonderful turn-of-the-century, science-book-esque evolution displays.

Catacombs turned marketplace.

A historic house left in "dramatic still life."

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

A mysterious artist-run cabinet of curiosities and library.

This shop and gallery is a modern-day cabinet of curiosities, unassumingly positioned along an urban thoroughfare.

This elaborately decorated, fairytale-like Romanian royal palace is one of the most striking castles in Europe.

A famous hotel houses an impression collection of mini dioramas and giant doll houses.