The longest living non-clonal organisms on Earth.

Macabre astrological automaton clock dating to the late 1400s.

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

The curious underground history of keeping Paris clean.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

France's most famous cemetery, with some of its most curious tombs.

An out-of-place slice of France, smack in the middle of Shanghai.

The fairy tale castle of the "fairy-tale king."

The original film set of Luke Skywalker's Tatooine home from the 'Star Wars' trilogy.

Slum Settlement Filled With Mountains of Garbage.

Founded as a refugee camp, now a popular tourist spot.

Vast stretch of tide-pools with a unique Moroccan charm.

An awe-inspiring mosque in Morocco with one of the tallest minarets in the world.

A walk-in working camera obscura produces 360-degree live images of the San Francisco coast.

The seawater playground of gilded-era San Francisco burned to the ground in 1966.

Carnivorous plants, medieval aphrodisiacs, and the largest original wood structure glass conservatory in the western hemisphere.

A masterpiece in Golden Gate Park by virtue of the artist’s debt.

Relics of the 1894 Midwinter Exposition continue to delight visitors today.

A winding path built in secret on the edge of the continent.

First point in the Struve Geodetic Arc, a 19th century undertaking to measure the Earth's size and shape.

The Guardian of Tallinn.

An empty relic of the Moscow Olympics crumbles away in Estonia's capital.

A subterranean house of worship carved right out of the bedrock.

Flamboyant architecture from the turn of 20th century.