Giant WWII fortresses that fired 8,000 rounds a minute, now home to thousands of pigeons.

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

This abandoned coliseum was intended to be a grand Nazi rallying ground before it was halted at the end of the war.

A castle from the Holy Roman Empire that hosts traveling youth... in its stables.

Maybe the only missile installed in a public park, this Cold War leftover was one of the first to carry a nuclear warhead.

3,200-square-foot mural inside Dartmouth Library depicts the history of America with images of human sacrifice, ancient gods, and other unspeakable terrors.

Tour the world's largest deep-hole dimension granite quarry, where you can view the plant where gravestones are made and roll a ball down the outdoor granite bowling alley.

One car at a time please.

The most famous location in China was home to whole dynasties worth of imperial rulers.

This ancient Chinese observatory still contains early astronomy technology.

Electrical pylon in the shape of Disney's beloved mouse.

The world's largest private aircraft collection.

The smallest post office in the United States is no bigger than a broom closet.

Former utopian colony based on the belief that the universe exists in a hollow sphere.

When you visit his grave, be sure to rub the Great Emancipator's nose for good luck.

One of the most powerful computers in the world can be visited by anyone who wants to experience more computing than they can handle.

An amazing collection of scale model ships.

Enormous statue of the Emperor of the Mongols.

The final resting place for the remains of 143 Habsburg royalty.

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

Church built on the site where the last tsar of Russia and his family were killed.

Russia's own leaning tower was built on a tragic historical fable.

Replica of mosque destroyed by Russia in the 16th century.

This North Korean pegasus statue was built as a symbol of the speed and perseverance of North Korean workers.