This tiny museum's sizable collection is jammed into a former underground public toilet.

This natural Icelandic fissure allows divers to swim right between two volatile tectonic plates.

This valley of hot springs and boiling mud pots is home to the record-holding "Geysir," which originated the English word.

These ominous lava formations were said to be an entrance to the netherworld so of course they inspired a famous metal band.

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

A sulfuric martian landscape that looks far better than it smells.

This tumultuous Icelandic lava field looks so alien European researchers want to use it as a stand-in for Mars.

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

One of the tallest buildings in Iceland, and perhaps, the most visually impressive.

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

Reminders of the Battle of Berlin still scar the railway.

Metro station with a claim to rock n' roll fame.

Tiny memorials honor individual victims of the Holocaust.

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

The world's first clock to use set theory as a measure of time required the invention of a new light bulb just to maintain its obtuse measurements.

The bunker where Hitler took his own life is hidden under this deliberately ordinary parking lot.

A tree-like building perches on its trunk in the Steglitz neighborhood of Berlin.

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

A fascinating insight into daily life in the Eastern Bloc.

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.

This hidden rooftop garden in downtown London offers a quiet respite from a bustling city.

The final resting place of a German diplomat's beloved companion.

A network of bells in the pubs and restaurants around Westminster alerts politicians when it's time to cast their votes.