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

The geographical center of Budapest is marked with a 10-foot-tall stylized zero.

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

Uh, pardon me, ma'am, but I couldn't help noticing that there's a Columbo statue in the middle of Budapest.

From Austrians to Nazis to Soviets, this historic Budapest fortress has a history as complex as the city itself.

The history of occult science is turned into a creepshow at this lurid Prague tourist attraction.

The first museum in the world devoted to sexual gadgetry.

This palatial spiral staircase was so unusual the name "snail" was given to the noble family who built it.

Physicist’s epitaph provides final confirmation to a career of turmoil.

Museum devoted to the artificial language of Esperanto.

Vienna's diversity-themed traffic lights were inspired by the Eurovision Song Contest.

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

Handsomely crafted representations of our round planet.

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

Double spiral staircases are not unheard of, but they are very rare.

The shell of a medieval fortress offers commanding views of the area it once protected.

Resting in the middle of an Austrian river, this sci-fi "island" lets people cross in neon style.

Austria's ultra-modern art museum looks like Cthulhu's giant alien heart.

The world's largest historic armory was established by independent citizens to defend themselves from the wars of larger forces.

Third time's a charm, or in this case, two testicles are.

A larger-than-life house of cards stands outside the house of a former fashion designer.

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

The burial place of an obscure North African saint was turned into a macabre body preservation factory for the 17th-century Neapolitan elite.

This shining multicolored metro station deep under Naples is said to be the most beautiful in Europe.