This local emblem is the oldest and largest dragon tree in the Canary Islands.

Visit a surreal landscape so otherworldly NASA actually used it to train the Apollo 17 crew.

Partially collapsed lava tube and cave system complete with concert hall, underground pond, and unique albino crabs.

A magical sinkhole on the Yucatán Peninsula is adorned with mini waterfalls and hanging vines.

A silly medieval mural preserved on the side of a Viennese house.

Vienna's giant wonder wheel had a starring role in one of the greatest noir movies of all time.

Op-art architecture designed for happiness.

The doodles of a genius line the walls of a secret room under the Medici Chapel, where they were hidden for nearly 500 years.

Renaissance villa and gardens complete with a tormented colossus.

An open-air museum in a mountain valley features works designed to blend in with—and disintegrate back into—their natural surroundings.

This crucial gathering spot along the "hippie trail" still displays old notes between traveling beatniks and backpackers.

The history of occult science is turned into a creepshow at this lurid Prague tourist attraction.

A collection of anatomical samples from one of the first anthropologists to suggest that humans reached North America by crossing the Bering Strait.

An extraordinary museum devoted to the pop art legend created by Slovak artists.

This mesmerizing medieval monastery-cave complex sits thousands of feet above ground overlooking a valley.

This memorial park stands on the site of one of the largest mass executions of the Second World War.

This spaceship-like Serbian monument reaches for the stars in celebration of the fallen fighters of fascism.

Legends of treasure and spirits flow from this this fairy tale-like oasis.

A wellspring of natural Viagra found in Bosnia.

This brutalist monument is inscribed with 9921 names of Yugoslav partisans who perished during WWII.

A forgotten and crumbling Yugoslav monument to the victims of fascism.

This abandoned Olympic skiing facility still bears the scars of the Siege of Sarajevo.

A field filled with carved medieval tombstones called stećak.

A former bank seized as a sniper vantage point during the Bosnian War is now a secret graffiti art gallery.