One of downtown Berlin's last reminders of its Communist past.

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

This water-tower-turned-high-end-apartment building was once the site of an early Nazi concentration camp.

Puppet theater and museum holding a collection of more than 300.

This street has over a half-dozen names, all at once.

A peculiarly shaped brass sculpture hidden in a courtyard in central Lviv

This micro-nation may be some sort of prank, but its constitution sure seems official.

The site of the first battle of World War II.

This Nazi ruin was the site where Hitler was almost blown up by a suitcase bomb.

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

Real bones which are said to have belonged to a Polish dragon.

The walls and ceiling of this Polish church are decorated with thousands of skulls, with another 21,000 skeletons just below.

An ornate plague column – built to celebrate life – claimed the lives of numerous artisans during its construction.

The Frank Zappa fan club erected this monument to their prog-rock hero to mark a new era of post-Soviet Lithuania.

While this monument tile is shrouded in mystery it also marks the end of the longest ever human chain.

Monumental sculptures guard many of the graves, transforming this necropolis into an open-air fine art museum.

A cheeky architectural easter egg.

The slender brass strip in Prague's Old Town Square was used to tell time from 1652 to 1918.

A statue honors the children who fought Nazis in Poland.

A national collection of Communist-era musical posters.

Poland's oldest salt mine has nearly everything one needs to live underground forever.

The silly symbol for an underground protest group is now scattered around the city.

These massive moving sand dunes have swallowed an entire village and are still on the run.

A striking public sculpture representing the period of martial law in Communist Poland.