Berlin rings in the anniversary with 200 events in key locations of the city. A new AR app even gives users an interactive experience with the former wall.

The Berlin Wall, approximately 27 miles long, is dismantled by a crane as East Germany begins to dismantle the wall on Feb. 20, 1990, near the Brandenburg Gate in East Berlin, as a crowd watches.

U.S. President Ronald Reagan, commemorating the 750th anniversary of Berlin, addresses on June 12, 1987, the people of West Berlin at the base of the Brandenburg Gate, near the Berlin Wall.

President Obama will deliver a speech to Berlin at Brandenburg Gate; Ronald Reagan delivered his famous %22tear down this wall%22 speech in 1987 at the gate ...

The Berlin Wall, approximately 27 miles long, is dismantled by a crane as East Germany begins to dismantle the wall on Feb. 20, 1990, near the Brandenburg Gate in East Berlin, as a crowd watches ...

A woman cycles past a part of the Berlin Wall with the Martin-Gropius-Bau gallery in the background in Berlin on September 24, 2012. AFP PHOTO / DAVID GANNON ...

8-1-1963, DEC 6 1969, DEC 10 1969A sentry fixes his binoculars on activity across the Berlin WallThe wall of iron, wire and stone went up in that heated summer of 1961.Credit: Flip Schulkearchiveblog ...

In this Nov. 11, 1989, photo, East German border guards are seen through a gap in the Berlin wall after demonstrators pulled down a segment of it at Brandenburg gate. (LIONEL CIRONNEAU/Associated ...

East Side Gallery 3-kilometer section of the Berlin Wall. Following the Wall's fall in 1989, ... The Brandenburg Gate is an ...

East Berliners stand on top of the Berlin Wall near the Brandenburg Gate, Dec. 22, 1989, after two crossings were opened, making the historic site a public place for the first time in 28 years.

On September 19, Germany will honor a speech, delivered 25 years ago, with a permanent plaque on the very spot where President Reagan gave it in front of Berlin’s Brandenburg Gate.

When Reagan said, “As long as the gate is closed, as long as this scar of a wall is permitted to stand, it is not the German question alone that remains open, but the question of freedom for all ...