101 years since the first electric traffic signals

They were put into place on the corner of Euclid Avenue and East 105th Street in Cleveland, Ohio, on 5 August 1914.  The innovation would have been overshadowed by the outbreak of WW1, however.

Until electric signals became widespread, the standard practice was for motorists to honk their horns when approaching intersections -- traffic signals made things a lot quieter as well as safer. (Google graphic)