William Smith's iconic "map that changed the world" is hidden behind a curtain in the Geological Society building.

An eerie, protected forest of old-growth oak trees, many of which are now dead.

A 300-year-old tea shop that brought tea to the English people, not to mention the Queen herself.

One of the few remaining casualties of the London Blitz, this destroyed church has become an enchanting public garden.

This symbol of Yugoslav liberation decorated with 620 carved heads of mythical creatures is now a forlorn relic of another time.

A Serbian church lit by chandeliers made of weapons.

Despite being pillaged and destroyed a number over times down the centuries, this historic church still sort of stands.

The bizarre rocks of Đavolja Varoš are the result of natural erosion.

A Red Cross memorial museum at the site of the Niš concentration camp that operated for four eventful years during World War II.

A grand Yugoslav memorial to the group of partisans who fought and died resisting western Serbia’s Nazi occupation.

This 14th century castle withstood years of battle but is now sliding off the hills into the Danube.

This memorial park stands on the site of one of the largest mass executions of the Second World War.

Structure built from the skulls of vanquished foes.

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

The walls of Germany's Parliament still show the scars of the Red Army takeover in World War II.

Someone loved this song enough to carve all of its lyrics onto a tree trunk in a Berlin park.

An eerie, derelict amusement park in Berlin.

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

Super-heavy Nazi architectural experiment.

A state-of-the-art medical facility from the Imperial era is now a derelict ruin.

19th-century scientists would make the pilgrimage here to verify the precision of their measuring sticks.

This elaborate Byzantine-style building was designed for a not-so-pretty purpose.

A quiet memorial to those who died saving others in the heart of the City of London.

The remains of an ancient Roman teenager are memorialized at the base of a modern London landmark.