Calgary Plus 15 map
The +15 system was conceived by Harold Hanen, who worked for the city from 1966 to 1969.
The +15 played a prominent role in a Canadian film called waydowntown.
The +15 network is comprised of 59 bridges (and counting).
The +15 system is named as such because the skywalks are about 15 feet above street level.
The first +15 skywalk opened to the public in 1970.
At 16 kilometers long, the +15 is the worlds most extensive pedestrian skywalk system.