A vast Communist-era exhibition space in the Bulgarian capital.

"Holy Wisdom" overlooks the city that became its namesake.

Sofia's legislative center is continuously reinventing itself.

A striking symbol of the Bulgarian capital.

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

A Bulgarian monument to Russia's role in World War II is constantly being painted in pop culture protest.

A turn of the century building boasting some of the most beautiful art nouveau architecture in Prague.

This tipsy office building in downtown Prague was originally called “Fred and Ginger.”

Steadily reminding Czechia of its past.

Macabre astrological automaton clock dating to the late 1400s.

Tiny communists hammer away on the Olomouc Astronomical Clock.

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

An underground city of salt.

This sprawling concrete suburb of Kraków was designed by the Soviet Union as the model proletarian city.

In the midst of a living monument to Soviet social engineering, Polish Catholics built this church by hand.

This man-made mound monument was built out of soil from all across the Polish empire.

The unsettling remnants of a torn down movie set lies nearby the ruined location of the actual Płaszów Labor Camp.

Poland's oldest surviving university building holds a wealth of historic science instruments including some used by Copernicus.

Beneath Kraków Old Town's main square lies a hologram-filled medieval market vampire graveyard wonderland.