Go surfing on this urban wave, "hacked" by local surfers.

The narrowest street in the world is in danger of closing up entirely.

Visitors may notice something strange walking through this quaint German town.

This former insane asylum now holds a pathological anatomy museum.

Macabre museum devoted to historical Viennese murders.

This series of Baroque passageways in Vienna's cultural center mix old architecture with modern art.

Visitors dating back to the 1600s carved their marks in the stones of the iconic tower.

Explore this medieval cathedral by trying to spot all the malevolent monsters hiding in its beautifully colored windows.

There has been an astronomical clock on this spot since the 14th century.

According to the local folklore, the myriad colors of this lake are the result of a lovelorn wizard's blunder.

Two very green residential towers cleaning the air in one of Europe's most polluted cities.

A master of trompe-l'oeil creates a stunning, tourist-fooling dome out of a flat ceiling.

This ship carrying cargo and four church bells for the Catedral Metropolitana Nossa Senhora Aparecida ran aground in 1968.

Rolling sand dunes of the Sahara... in the middle of the Atlantic Ocean.

Pilgrimage site for star-crossed lovers.

An enormous pair of straw sandals woven in the traditional way—to keep demons at bay.

This enormous monument is one of the most iconic structures in Tokyo, rudely nicknamed "The Golden Turd."

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

Beautiful Austrian natural history museum with carved ceilings and row after row of ancient taxidermy.

Baroque celebration of the end of the Great Plague of Vienna.

The topiary maze at the Habsburg hunting lodge.

A tropical paradise just a short trip from the opera house is filled with beautiful winged creatures.

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

This 14th-century temple is also known as the "Temple of the Golden Pavilion" for its gorgeous gilded reliquary hall.