The White House announces President Obama will speak at the Brandenburg Gate in Berlin later this month:
"During his visit to Berlin, Germany, on June 19, at the invitation of Chancellor Merkel, President Obama will speak at the Brandenburg Gate. President Obama will speak about the deep and enduring bonds between the United States and Germany, the vital importance of the transatlantic alliance, and the values that bind us together. The President looks forward to meeting with Chancellor Merkel, and speaking directly to the German people. Further details will be provided at a later date."
Obama, as a presidential candidate in 2008, spoke in Berlin:
He addressed Berliners not just as an American citizen, but also as a "citizen of the world."
It's also the site of Ronald Reagan's famous "Tear Down This Wall" speech: