First Tri-Color, Four-Directional Traffic Signal, 1920

Summary

Detroit traffic officer William Potts created this three-color, four-way traffic signal in 1920. Previous illuminated signals used only red and green lights. The addition of an amber "caution" light made driving safer and the three-color signal became the standard by the mid-1930s. This first traffic light was installed at Woodward Avenue and Fort Street in Detroit, Michigan.

Detroit traffic officer William Potts created this three-color, four-way traffic signal in 1920. Previous illuminated signals used only red and green lights. The addition of an amber "caution" light made driving safer and the three-color signal became the standard by the mid-1930s. This first traffic light was installed at Woodward Avenue and Fort Street in Detroit, Michigan.

Artifact

Traffic signal

Date Made

1920

Creators

Potts, William L., 1883-1947 

Place of Creation

United States, Michigan, Detroit 

Creator Notes

Designed by William L. Potts of the Detroit Police Department in Detroit, Michigan.

Driving America
 On Exhibit

at Henry Ford Museum in Driving America

Object ID

38.537.1

Credit

From the Collections of The Henry Ford. Gift of City of Detroit Police Department.

Material

Metal
Glass (Material)

Color

Red
Yellow
Green

Dimensions

Width: 10 in

Length: 24 in

Depth: 10 in

Related Content

Connect 3

Discover curious connections between artifacts.

Learn More