A lone cannonball remains lodged in the walls of the Hotel de Sens as a sober reminder of a revolution.

Paris' linguistic guide to the international language of, yes, love.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

A diminutive statue that was inspired by the sculptor's own daughter.

The true meaning behind this sculpture remains unknown.

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

Late at night, the bust of the "Dracula" actor was snuck onto the facade of this Budapest castle.

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

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

Budapest's Communist-era statues, banished to the suburbs.

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

A Trabant car, a kangaroo statue, and a plethora of plants take over this abandoned-factory-turned-bar.

This off-beat, quirky communism-themed bar isn't afraid to poke fun at its history.

This Hungarian castle was built out of cardboard and wood until it proved so popular that it got upgraded to stone.

Built in 1870 at the bridge that connected Buda and Pest, this spectacular incline railway was almost lost forever during World War II.

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

Museum dedicated to the terror regimes of Hungary.

A trail of iron footwear stands as a monument to the thousands executed along this riverbank during WWII.

A series of caves under Castle Hill that once held the prisoner Vlad Tepes, better known as Count Dracula.

This Budapest bar allows drinkers to leave their mark on the walls, floor, and even ceiling.

A half-buried vehicle in Prague's is the latest iteration in a long-running piece by Czech artist David Černý.

Straight out of a nightmare, barcode-faced babies climb up and down Prague's television tower.

Bullet holes in the church wall are a reminder of the violence that followed the assassination of a high-ranking Nazi officer.

The slender brass strip in Prague's Old Town Square was used to tell time from 1652 to 1918.