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

Dedicated to a synagogue that was destroyed after having survived World War II.

This Slovakian statue of an emerging sewer worker might just be a bronze peeping tom.

A sculpture of a beloved local figure, who tipped his top hat to everyone he passed on the streets of Bratislava.

An ode to a soldier who came to town, fell in love, then began making his own sparkling wine.

Brass plaques embedded in pavement preserve the memories of those who lost their lives at the hands of Nazis during World War II.

The former Nazi concentration camp stands as a museum to remember this dark chapter in European history.

An underground city of salt.

At first glance, this area seems like just another city park, but the lush landscape hides a dark past.

St. Mary's features one of the most spectacularly decorated cathedral interiors in all of Europe.

The final resting place of more than 200,000 people, this is one of the largest cemeteries in Europe.

A bronze replica of an elm tree that honors the victims that perished in Pawaik Prison.

A tribute to the Polish insurgents who fought in the failed attempt to end their city's Nazi occupation.

An artificial date palm stands as a memorial to Warsaw's Jewish community.

The oldest museum in Borneo is a cornucopia of rare taxidermy and human skulls.

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

A plaque bearing the names of those who dedicated themselves to protecting Budapest's Jewish population during World War II.

The metal leaves on this tree are engraved with the names of Holocaust victims.

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

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

A triumphant marble and bronze fountain depicting a 15th-century Hungarian king and his hunting party.

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

Next to the Malaysian Prime Minister’s office stands this rose-colored mosque.

Holy Hindu shrine in an enormous, monkey-filled limestone cavern.