Vortex-shaped aquarium hosts Europe's largest school of piranhas and other ocean creatures.

Secret Swing.

A collection of more than 12,000 shoes, displayed in a building shaped like a shoebox.

The oldest landmark of Toronto is a testament to shifting sands.

One of the Seven Wonders of the Modern World holds the world's tallest metal staircase.

Willy Wonka would love this weird half-a-home.

This massive, ancient stone was disassembled and then put back together again.

This "Palace of Purification" has made many film appearances as a dark and sinister headquarters.

These strikingly barren, rolling red hills were caused by bad farming practices.

Legends surround an ancient tree trunk riddled with nails for good luck.

305 homemade stone stairs wind their way up the Hamilton escarpment.

"The most colorful grottoes of the world.

A sprawling Baroque park with 300-year-old hydro-pneumatic waterworks.

Manhattan’s Battery Park has a whimsical carousel full of spinning, glowing fish.

A 98-room castle in the middle of Toronto that bankrupted a 19th century electricity multimillionaire.

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

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

The crypt of the imposing Stephensdom holds royal intestines and thousands of skeletons.

Silent memorial, using bone conduction to take people back to the Dresden Bombing of 1945.

A unique hanging cable-car navigates through Dresden, the oldest suspension railway in the world.

Underneath the city that invented pilsners are a series of historic tunnels that have been storing beer for centuries.

Two monstrous faces loom over a village in Czechia.

Monument to a suicide protesting the Soviet invasion.

A mocking tribute to the past and modern leadership of Prague.