Visitors are treated to a stained glass kaleidoscope interior inside this work of art.

A lush indoor jungle fills this bustling Madrid transportation hub.

Madrid's romantically ornate crystal palace has been offering shelter to plants and art for over a century.

Considered the birthplace of the Copper Age and Bronze Age, the river is tinted red from 5,000 years of mining.

This museum is a portal to 20th-century Denmark.

The last Viking king of Denmark is buried inside the crypt of this cathedral.

Generations have refused to move this doll from its dusty resting place to preserve a castle from a watery fate.

Inside this Jewish cemetery is a memorial to soldiers who deserted the German army and were executed.

A massive base for the Nazis' most formidable weapon in the Atlantic.

This historic island prison holds one of the dungeons from the Count of Monte Cristo even though it is a work of fiction.

This French ghost town from World War II has been left as a memorial to German atrocities during World War II.

This 1,300 year old monastery built atop a single rock was once only accessible depending on the whims of the tide.

In Northeastern Iceland lies something of an oxymoron: a steaming desert.

A bit of the Berlin Wall was gifted to the Icelandic capital to commemorate the 25th anniversary of German reunification.

This modern monument to pagan belief looks like it was transported straight from ancient times.

This elegant arc of a waterfall marks a religious turning point.

It houses the remains of a 17th-century version of the Titanic.

1,300 chamber pots and their eccentric collector.

These former Nazi anti-aircraft towers offer a singular view of the north of Berlin in the summer, and a sanctuary for bats in winter.

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

A tour of underground Berlin takes you through WWII air raid shelters and tunnels used to smuggle people out of East Germany.

The fairy tale castle of the “fairy-tale king,” this was also the inspiration for Disney’s “Sleeping Beauty.”

The unique waterfall in Iceland's south features a backdrop of geometric black lava columns.

This beautiful, historic church looks like something out of a simpler past.