A marvel of Byzantine engineering under the streets of Istanbul.

Hans Christian Andersen for the postmodern world.

The de facto symbol of Copenhagen is this bronze fairytale which cannot seem to keep its head for very long.

This former Masonic lodge has been transformed into part museum, part bar, all awesome.

The iconic boulevard is the perfect place to catch sight of a bicycling skeleton, a levitating Satan, or a chef with his head stuck in a pizza.

Mountain where Jesus was first tempted by the Devil.

An unusual stroll through gentlemen's erotica demonstrates that pornography is timeless.

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

Gargantuan home of Russian science.

This building holds the embalmed remains of the leader of the Bolshevik Revolution.

This walkway is so narrow it needs its own light to stop pedestrian traffic jams.

A surreal statue honoring Prague's favorite literary son.

Despite attempts by local police to discourage it, Beatles-inspired graffiti has been a means for artists to air grievances for decades.

Around 100,000 bodies are buried below the medieval headstones, many of which mark graves with multiple bodies stacked up to 12 deep.

Macabre astrological automaton clock dating to the late 1400s.

Berlin's beloved bear is immortalized at the Museum für Naturkunde.

Cold war icon and onetime "hole" in the iron curtain.

Blitzkrieg bop your way through Berlin's Ramones Museum.

The bunker where Hitler took his own life is hidden under this deliberately ordinary parking lot.

On the Spree bank, discover one of the last reminders of a symbolic wall that divided, and was torn down by the people.

Thousands of coffin-like pillars make up this controversial Holocaust memorial.

The most visited, and possibly most controversial, museum in Germany.