Twenty-five years ago this week, the unthinkable happened. On November 9, 1989, East Germany opened the gates, allowing its citizens to travel west. On a recent tour of Berlin, I was struck by how often the "unthinkable" suddenly becomes reality,
Having been a no man's land for many decades, Potsdamer Platz has returned to the middle of the now-reunited city. A look at what's changed and what remains the same at Berlin's ever-controversial plaza.