While there really is a day of jubilee for us in Germany, I just want to remind that 136 people were killed between 13 August 1961 until 9 November 1989 when trying to flee over the Berlin wall. (Official number, many estemate it to be higher.)
In 1965, I stayed with my school class in a hostel next to the ruins of the Anhalt station (
Anhalter Bahnhof/
Askanischer Platz). From some windows of that building (originally Siemens headquarters for engineers, than headquarters of the VARTA battery company, bombed during the war, afterwards at first refugee "hostel", later accomadation for schools and groups - today newly built offices for the daily paper
Tagesspiegel) we could overlook the Potsdam place.
During the one week we stayed there, we've seen/noticed two failed attempts to "cross" the border. You hardly could sleep any night (if your room was an the "wrong" side of the building) due to the flood and searchlights.
When we walked to the
U-Bahn ("Metro") station, we had to walk along the wall. Nearly every time, our group was accompanied, by a West-Berlin policeman and an armed custom officer.