Places KarlPopper Wants to Go

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

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

Museum devoted to the artificial language of Esperanto.

Handsomely crafted representations of our round planet.

A patriotic medieval knight in driven-nail armor raised money for widows and orphans of WWI.

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

Vienna's underworld of tunnels and subterranean rivers made an iconic appearance in a 1949 Orson Welles film.

This sculpture of a rhinoceros suspended above a city square is meant to evoke the weight of the human condition.

A Museum with a collection of 40,000 matchboxes.

A maze of underground tunnels beneath one of the most beautiful forts in Serbia.

Backwards hour and minute hands and a timing mechanism that fluctuates with the temperature led to this clock tower's local nickname.

Solar observatory doubles as a daring display of Expressionist architecture, much to Einstein's chagrin.

This statue of the famed author, actor, and journalist is made entirely of screw-nuts.

This statue of a 15th-century Hungarian military and political figure has become known for its resemblance to a particular cartoon knight.

A small memorial to a deadly night in Serbia that shook the world before it was swept under the rug.

This statue of a goat in boots is meant to represent the European Union.

Ride in 1960s style on the private luxury train Marshal Josip Tito used to travel around Yugoslavia.

A museum dedicated to the former country.

An abandoned monument remembering the "Pančevo Holocaust" now stands as a shadow of its former self.

These stairs feature the names of Zemun's most famous faces.

This stone figurine was made more than 6,000 years ago and depicts a female deity of the Neolithic Vinča culture.

A well preserved medieval fortress in Vojvodina.