This building displays the scars of the “Dekemvriana,” a dark time in modern Greek history.

The only surviving choragic monument is a trophy awarded in 334 BC for the winning dramatic chorus.

These ancient ruins hide in plain sight next to a dessert shop.

View the ancient remains of buildings and the ancient "River of Hades" before hopping on a train.

The ruined doorway is a portal to the building's turbulent and torturous past.

Luminaries of all stripes have sipped strong Greek coffee at this cafe since 1839.

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

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.

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

Sofia's legislative center is continuously reinventing itself.

This communist behemoth is the heaviest building in the world and a legacy of a brutal regime.

This memorial to the victims of the Romanian Revolution of 1989 is often compared to a potato on a skewer.

Never actually a tree at all, this spot was the site of London's public hangings for nearly 600 years.

These marks in Myddelton Passage aren't your run-of-the-mill vandalism, and they weren't made by your typical vandal.

The last remaining example of the boatmen's perches that once dotted the south bank of the Thames.

A hands-off space for graffiti artists to hone and display their skills.

Pop culture has helped to keep this iconic British building from being destroyed.

This building contains a door only used by members of the royal family.

One of the few remaining examples of 19th-century London’s attempt to clean up its reputation.

The pretty iron lamp is a reminder of the architecture underneath London's streets.

England's most famous front door has an accidental doppelganger.

A living memorial to the trees London lost during the Great Storm of 1987.

An unusual ode to the late Irish playwright, complete with a squiggly bust and coffin-shaped bench.