This mundane shopping plaza is named after a gruesome piece of flotsam.

A line of disused military bunkers built to defend against Nazi invasion lies hidden on the outskirts of the city.

A unique hotel for the artistic soul.

A relic of the Cold War tucked away in the forested hills above Bratislava.

Possibly the world's largest hourglass only needs to be reset every New Year's Eve.

Apartment complexes built into huge repurposed natural gas tanks.

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

A giant glider—designed by the father of the Rubik's Cube's designer—now soars within a shopping mall.

The largest statue of this convex, homogeneous object with just one stable and one unstable equilibrium point.

From cartoon characters to tiny tanks, a guerilla sculptor's little bronze statues are hidden throughout the city of Budapest.

This quaint Hungarian railway system is operated exclusively by children between the ages of 10 and 14.

The mummified right fist of a 1,000-year-old saint-king sits inside an ornate golden reliquary.

Once the home of a hermetic monk, this cave now houses a small church.

This Byzantine Church was moved from Paris to Athens block by block.

Plaques celebrating Lithuanian writers freckle a wall of this picture-perfect path.

Things aren't quite what they seem at this mind-bending museum.

A narrow strip of land is home to the tallest migrating dunes in Europe.

A spectacular cave and a beguiling lake.

This Ottoman-era church is hidden amid a busy tourist area.

A 2,000-year-old computer demonstrates remarkable engineering and astronomical precision.

A swaggering, monumental souvenir of the most extravagant party Montreal’s ever thrown.

Two identical statues by Fernando Botero, one blown to pieces in a terrorist bombing, the other donated as a gift for peace.

A church dedicated to the Mexican skeleton saint.

A massive sustainable farm designed by the mastermind behind Central Park.