An ancient oak forest where, legend has it, a wedding party was magically transformed into trees.

The secret cells in the basement of the KGB's Estonian "Grey House" have been preserved as a grim Cold War museum.

This medieval Estonian tower provides access to a series of tunnels that have been home to soldiers, punks, and fine art.

An underground nightclub helped spark a "Singing Revolution."

A secluded art gallery hidden within the cellars beneath Tallinn’s medieval monastery.

During the Soviet era, the spire of this longstanding church was used as a radio transmission tower.

A massive tribute to Estonian history and culture.

This curious sculpture represents the perseverance needed to take to the skies.

A helicopter memorial commemorating what was once the only way to access this West Berlin exclave.

A local train station entrance hall doubles as a sanctuary for barn swallows.

A memorial commemorating the place where Truman gave the order to deploy the first nuclear bombs on Japan.

The home of president Truman during the Potsdam Conference, and the place from which the atomic bomb strike on Japan was triggered.

This spectrum of a star was observed by one of the world's most accurate spectrographs. 

A historical observatory still in use by modern astronomers.

The home of Joseph Stalin during the Potsdam conference.

Germany's Glienicke Bridge has a shady history of clandestine meetings, espionage, and spycraft.

A quaint Russian village in the middle of a German metropolis.

A tree meticulously shaped and trimmed into the shape of an elephant.

One of the few Tudor palaces in Germany, which hosted a historic WWII meeting.

A second hand shop that enabled the plan of Germany's most iconic conman.

If you visit the burial place of King Frederick the Great, you'll likely find a couple of potatoes sitting on his tombstone.

The "Prussian Versailles" that is as glorious today as when it was built.