This ornate Victorian marketplace was the setting for Diagon Alley and the Leaky Cauldron in the Harry Potter films.

A former steam-powered mill from the 1800s is now an industrial park with a giant steel dragon slide.

A vista of the city and sea from atop the little-known viewing deck on an unassuming Columbus statue.

This former Baroque palace on the historic Calle Montcada is a rare architectural gem and was once the meeting place of an aristocratic scholarly society.

Step inside the first house designed by Catalan architect Antoni Gaudí, considered to be one of the first Art Nouveau buildings.

Mountain where Jesus was first tempted by the Devil.

Week-long block party becomes a competition for the best decorated street.

This cemetery features modernist statues as strange as its name.

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.

One of Antoni Gaudí's most classic buildings is well-known for its "dragon-back" design.

A replica of the Liberty Bell rang daily from West Berlin's City Hall throughout the Cold War.

Tiny memorials honor individual victims of the Holocaust.

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

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

One of the world's tallest statues is also one of its most hated.

Gargantuan home of Russian science.

Home of the future Emperors of Russia.

The tallest hotel in Europe.

World's largest bell sits on the grounds of the Kremlin in Moscow.

Former headquarters of the KGB.

The gorgeous entrances into the city's underbelly look more like grand halls than subway stops.

Gutted airplanes slowly decay in a Florida field.

A sprawling nature preserve harbors the world's only living dragons.