Berlin was divided from 1961 to 1989. That all came to and end on November 1989 when the wall was taken down for good and Berlin was reunited. Some people were happy about the wall being removed others hated the idea. Either way if you were there during those events you witnessed history. Here are some pictures taken during the destruction of the wall.
By slicing into the iris of the eye, she is expressing her desire to literally see more of Berlin. The symbolism of the image of an eye on a wall, and the inability to see through it is profound. She is seeing what had been unseeable for so long.