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

The old observatory in Copenhagen has a spiral corridor used as a racetrack.

This stunning iron gate designed by Modernist architect Antoni Gaudí is filled with mythic symbolism.

The London pub overlooks where the Mayflower was moored before setting sail for the New World.

The tallest bridge in California was constructed for a project that was eventually cancelled.

This statue was given to France by the United States to commemorate the centennial of the French Revolution.

One man's exploration of the human form, including the bizarre and delightful "Man Attacked by Babies."

This misspelled graffiti reappears every time it is removed.

A cathedral resurrected from the ashes of one of Europe's greatest urban fires.

The church's remarkable frescoes incorporate Finnish artist Hugh Simberg's trademark themes of death and the supernatural.

Nuclear waste experts study this prehistoric crater lake to envision landscapes one million years in the future.

This insurance company building reminds customers that witches, bears, and gnomes are out there, best be insured.

This irregularly shaped sea fortress has defended not one but three different sovereign states.

This restaurant combines two Finnish traditions in one place: warm-weather relaxation and outdoor carpet-cleaning.

L. Frank Baum wrote part of the "Wizard of Oz" series in this wooden Victorian beach resort.

The blinking light atop the iconic landmark has been sending secret messages for decades.

The only remaining arch of the oldest stone bridge in Rome stands in the middle of the Tiber.

Murals made with millions of colorful stones adorn the abandoned building.

Bullet holes in the church wall are a reminder of the violence that followed the assassination of a high-ranking Nazi officer.

A surreal statue honoring Prague's favorite literary son.

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

A steampunk-styled three-floor factory churning out art, activism, and electronic beats.

A series of playful yellow penguins share a serious message about the environment.

A turn of the century building boasting some of the most beautiful art nouveau architecture in Prague.