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

The art museum is decorated with creatively remodeled pre-Nazi swastikas.

The gilded, masterful astronomical clock will calculate time, dates, and planetary positions for thousands of years to come.

Copenhagen's celebrated theme park and gardens.

Danish tourist destination well known for open stalls where vendors sell marijuana on the street.

What was once a true peninsula has now been filled in, causing the water to recede and leaving many streetside "waterfronts" and landlocked "islands."

The remnants of a Gilded Age elegance preserved in the middle of a stark modern tower.

The world's largest piece of copyrighted artwork.

More than 200 unconventional musical instruments that anyone can play.

With some 500,000 books across five buildings, this bookstore is a reader's paradise.

Outstanding taxidermy dioramas showcase the grandeur of the continent's wildlife with spooky realism.

A mysterious echo seems to defy the laws of acoustics.

Colorful clay cliffs tower over an unofficial nudist beach on Martha's Vineyard.

A perfect circle of twenty-four mysterious holes dates back to prehistoric time.

This abandoned Slovenian military barracks has become a punky-political art squat.

This demon atop the Notre-Dame de Paris looks utterly bored.

These mysterious Viking chess pieces spent centuries hidden on a remote Scottish island.

Every color in the rainbow awaits.

Peace Park and the Atomic Bomb Dome.

A plaque marks the site directly below the mid-air detonation of the atomic bomb over Hiroshima.

This 700-year-old street food market features baby octopus and soy donuts.

A beautiful bamboo trail tucked in this famous Japanese Shrine.

The sound of swaying stalks in this stunning grove has been named a governmentally recognized sound.

Go through the looking glass in Tokyo's Wonderland-themed shop.