The skeletal frame of a decommissioned gas-pumping station offers breathtaking views of greater Berlin.

Beneath the impressive baroque cathedral that rises from the center of Berlin lies the largest collection of Prussian royals in the world.

The site of the famous Nazi book burning campaign of 1933 remembers its "Night of Shame".

A unique Holocaust memorial tells the personal stories of the Jewish residents exiled from greater Berlin.

Super-heavy Nazi architectural experiment.

Started as a kitchen garden, now the second largest botanical garden in the world.

Synagogue built from the stones of Solomon's temple contains the golem of Prague.

The final resting place of many of Germany's most famous communists.

An old department store turned Nazi prison turned artist commune.

Reminders of the Battle of Berlin still scar the railway.

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

Floating swimming pool within a moored vessel.

This futuristic German spa allows visitors to float in a pool of salt water while zoning out to underwater techno.

This Parisian fountain is a little bit fantasy and a little bit nightclub.

Remains of Roman amphitheater hidden in a sleepy quarter of Paris.

Twelve grave-faced marble angels guard the emperor's tomb at Les Invalides.

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

This Parisian café sticks almost exclusively to an ethos of reuse.

Notorious artist squat renovated into legal studios.

A curious collection of locks and keys.

The spiral staircase hidden inside this giant Parisian column was likely built for Catherine de Medici's astrologer.