What are 4 important events that happened at the Berlin Wall or pertained to the Berlin Wall?

I am doing a report on various locations, monuments, exhibits etc. for a final project in my ap cl. I picked the Berlin Wall as one of my locations and I need at least 4 events that happened at or DIRECTLY relate to the Berlin wall. I can only think of it being torn down and erected. So any event you can think of besides those 2 would be great. Thanks in advance!