A 12th-century fortress containing some of Berlin's oldest buildings.

After a nearly successful attempt on Hitler's life, the conspirators met their fate in the courtyard of this Berlin building.

The site where a plot to assassinate Hitler was planned—and its conspirators were executed—is now a powerful memorial to the German resistance during World War II.

The bunker where Hitler took his own life is hidden under this deliberately ordinary parking lot.

A historic fire call point.

A monument to the three wars that led to German unification towers within a Berlin traffic circle.

An astonishingly accurate water clock that doubles as an hourly spectacle in this Berlin shopping area.

The world's first clock to use set theory as a measure of time required the invention of a new light bulb just to maintain its obtuse measurements.

An imperial church bombed to ruins during WWII now stands as a jagged memorial.

A memorial in the Tiergarten is a reminder of the suffering inflicted on homosexuals by the Nazi regime.

One of the world's heaviest musical instruments towers within a popular urban park.

A museum in the building where Nazi Germany signed its surrender tells the story of World War II from the Soviet perspective.

A towering monument to war, located on a beautifully peaceful hill.

This public observatory is home to the "celestial cannon," the longest pointable telescope in the world.

For patriotic Russians, this memorial honoring the Soviet soldiers who died liberating Berlin in 1945 is the most sacred location outside of Russia.

This monumental work of art symbolizes the coming together of a previously divided city.

This platform is now a memorial dedicated to those who were deported during the Holocaust.

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

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

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

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

The site of the original experiment that would be used to disprove the theory of luminiferous ether.

One of the largest refracting telescopes in the world, and the first built specifically for studying astrophysics.

Solar observatory doubles as a daring display of Expressionist architecture, much to Einstein's chagrin.