An underground city of salt.

The 1936 Summer Olympics site is a crumbling remnant of sportsmanship and a history its host country would like to forget.

The oldest amusement park in the world has been providing a nice spot to have some fun since the 1500s.

This colorful artistic feature atop a Danish art gallery allows visitors to stroll through a rainbow.

This Danish park has celebrated the American independence day since 1912.

Four alabaster giants contemplate the tides on the shore of Denmark.

The northernmost point in Denmark is a turbulent sandbar created by two clashing seas.

Opulence and fantasy collide in this royal chair which is supposedly made with unicorn horns.

A miniature city, once ruled by the Queen of the Netherlands.

Single runway interrupted by a busy road that cuts across its middle.

Sweden's "good old days" painstakingly re-created in a model village.

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

A little sculpture with a large wardrobe.

Climb inside an iron crystal magnified 165 billion times its normal size.

An abandoned set from the 1980 film "Popeye," claimed and repurposed as a theme park by creative locals.

Berlin's old airport.

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

The largest collection of hair jewelry in Europe reminds you how creepy 19th-century love was.

The original home of the Lego has a huge amusement park dedicated to the iconic plastic toy.

Denmark's famous pseudo-hill.

Old Danish castle immortalized in Shakespeare's Hamlet.

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

Danish observation tower designed to look like a giant beer bottle.

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