Chaustrasse Gate was a major checkpoint between East and West Berlin, and the subway stop to reach it is Schwartzkopff St. The only indication of the Wall's presence is a small plaque in the street and an information sign on the sidewalk. You can see where the wall was: there are double bricks crossing the road that indicate its former presence. The Watch Tower, a 15-minute walk from there, is now a memorial to Gunther Litvin, and Gunther's brother is the curator of the Tower. This is one of the last observation towers left standing, and you can climb the ladder to the third floor observation area. Close by is the Invaliden Cemetery, which is a historic cemetery partly destroyed in the Cold War.