Walk through Czech history in Prague's largest graveyard.

Be(w)ar(e) the moat around this historic Czech castle.

World's largest barrel containing an inn.

Sitting in the basement of a castle, the largest wine barrel in the world is bigger than most apartments.

An eerie, derelict amusement park in Berlin.

This sculpture by artist Fritz Keonig survived the 9/11 attacks and now stands as a monument to the victims.

Scattered throughout London are ancient remnants of the city's former bounding wall.

A cluttered and astounding collection of antiquities and curiosities.

The final resting place to 300 Victorian-era pets hides inside the city park.

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

Banksy gives themself artistic license with this piece of London street art.

Rebuilt remains of a temple to Roman god Mithras.

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

Sofia's legislative center is continuously reinventing itself.

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

A striking symbol of the Bulgarian capital.

Two stone columns flank the grand Venice square, but there were supposed to be three.

A public work of art that also provides some relief from the summer heat.

This jaw-dropping 19th-century bridge uses its reflection to form what appears to be a perfect circle.

Ruins of a German castle on top of a towering stone pillar.

A famous big wave from Japan serves as a tribute to the victims of the disastrous Elbe flood.

Tourists often confuse this beautifully ornate former cigarette factory for a mosque.

This Dresden church was purposely rebuilt Protestant after being demolished in World War II.

Slaughterhouse Five opens its dank doors to fans of Kurt Vonnegut.