After an Illinois church was struck by lightning and burned down, Frank Lloyd Wright designed this replacement.

Northern Europe’s largest castle ruins sit precariously on an island cliffside.

This cave at the base of an unusually shaped cliff is said to be inhabited by a mythical forest enchantres from Scandinavian folklore.

It is said that each of the white stones in the red facade of this medieval house represents the head of a murdered Swedish noble.

A heated statue pays tribute to one of Sweden's great actresses.

A concrete mushroom that divided Stockholm residents for nearly a century.

The 19th-century home of Count and Countess von Hallwyl is now a museum.

Sound travels strangely in this underground whispering gallery.

This pair of unsuspecting buildings are in fact the very first modern skyscrapers in Europe.

An imperial church bombed to ruins during WWII now stands as a jagged memorial.

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

Once the world's most modern observatory, this building is now a private school.

This bridge's unique architecture honors nautical heritage and encourages self-awareness.

Six ravens are kept captive (but well-fed) at the Tower of London to prevent the fall of the Crown.

One of the tallest waterfalls in Africa is also home to a population of monkeys who enjoy the waters and the occasional guest.

The other side is actually green.

An icon of International Style architecture on the outskirts of Rotterdam.

This poignant sculpture of a gnarled weapon is a symbol of non-violence.

Swedish mice can dine at the Nuts of Life restaurant or take a date to the amousement park.

The palace for King Gustav III was never completed, but the foundation remains tucked away in this city park.

The Swedish flag over this small naval fort signals that the nation is at peace.

A golden plaque marks the site of the mysterious unsolved assassination of the former Swedish prime minister.

Street artists transformed this abandoned industrial neighborhood into one of Europe's largest graffiti exhibitions.

Now a hotel, this former bank was the site of a robbery that spawned a psychological phenomenon.