The commemorative stone column conceals a secret laboratory.

The perfectly preserved underground rooms where Churchill plotted the war against Germany.

A statue of the legendary Celtic warrior queen who fought the Roman invaders stands in one of the cities she once destroyed.

One of the greatest movie directors of all time lived and worked in this London flat from 1926 to 1939.

The Metropolitan Police refurbished the blue box (perhaps not coincidentally) the same year "Doctor Who" returned to TV screens.

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

This German monument honors the so-called "Prince of Mathematicians."

Bursting forth from a historic German neighborhood, these day-glo palaces are now a bright fixture in the town.

Old cabin-like homes in a rural community untouched by time are known for their vibrant and colorful window shutters.

The bridge that cost Germany a World Heritage Site.

Art installations, derelict railcars, and endangered grasshoppers all call this south Berlin park home.

A museum that chronicles the history of the Nuremberg Trials for Nazi war criminals in the building where the trials were once held.

A famous big wave from Japan serves as a tribute to the victims of the disastrous Elbe flood.

The “Coin Cabinet of Dresden” houses a collection of over 300,000 numismatic artifacts, one of the largest of its kind in Europe.

You've probably seen these distinctive orange-tiled columns on the big screen.

A tribute to the first human in space.

This Polish cave has housed a dragon, a brothel, and an enduring legend.

Crosses of all shapes, sizes and colors litter the mountain, the site of a huge yearly Orthodox pilgrimage.

Germany's last remaining Lenin statue has become a lightning rod of debate about the country's divided past.

Retirement home for giant obsolete machines.

This now-defunct synthetic fuel plant was once a major cog in the Nazi war machine.

What was once an underground Nazi city is now Europe's largest bat reserve.

A statue of Vladimir Illyich Lenin guards this abandoned building in the "Forbidden City."

The relics are stored in a silver reliquary, where they can be seen through glass.