The ghost town left by the worst nuclear disaster of all time is being taken over by nature and urban explorers.

The medieval prince founded the first library in Ukraine at Saint Sophia's Cathedral where he was interred.

The deepest metro station in the world.

An Art Nouveau building covered in animal gargoyles and grotesques.

A reconstructed medieval gateway that was the magnificent entrance to the capital city dating back to 1037.

340-foot statue built to honour the Heroes of the Soviet Union.

This abandoned Soviet circus is slowly being restored to its Communist-era glory.

Elaborate mansions built by Roma residents in Soroca to show their success after centuries of discrimination.

Seventy-five miles of limestone caves host more than a million bottles of wine beneath a sleepy Moldovan town.

A forgotten remnant of the Soviet Union, Transnistria is an unrecognized country hidden behind a heavily militarized border between Moldova and Ukraine.

The largest wine cellar in the world is a 150-mile network of underground caves near the capital of Moldova.

This statue in Plaza San Francisco commemorates a beloved figure from 1950s Havana.

Besides being home to cave paintings and pre-Columbian Cuban archaeological remains, you get to take a boat through this stalactite and stalagmite covered cave.

A colossal statue with a controversial past, forgotten for more than 30 years.

An old slave lookout in Cuba's historic sugar cane fields.

Neo-cave art on the macro scale.

After the Cuban Revolution, the famous rum company had to leave their swanky headquarters behind.

This imposing memorial contains the remains of Che Guevara — and 29 other guerrillas who died with him in Bolivia.

The house that birthed The Old Man and The Sea is now a museum devoted to the old man who wrote it.

No one knows the meaning behind this giant sculpture of a nude woman with a fork riding a rooster in Havana.

Once a favorite playground for the world's most illustrious guests, Hotel Nacional's secret weapons and bunkers reveal a more menacing side to its golden history.

A focal point of the Cuban government, this city square features one of the most iconic images in the country.

This subterranean disco dance club in a Cuban cave comes with bright lights and a dark legend.

The enigmatic skull gazes out over the ruins of a once-great Mayan city.