The Wall in numbers

Total length of the border to West Berlin 155 km
Inner-city border between East and West Berlin 43 km
Border between West Berlin and the GDR (“outer ring”) 112 km
Border crossings between East and West Berlin (roads/railway) 8
Border crossings between the GDR and West Berlin (roads/railway) 6
Observation towers 302
Bunkers 20
Dog runs 259
Anti-vehicle trenches 105,5 km
Contact or signal fences 127,5 km
Border patrol roads 124,3 km

(As of 31.07.1989, Lapp/Ritter, Die Grenze, 1997)