Los Angeles Railway rerouted many lines on May 9, 1920,[2] assigning them letter designations the following year.

The 3 West Adams and Lincoln Park Line also ran on Main Street.

A branch at Edgeware Road opened in 1934, and the main service was rerouted on this line starting in 1938.

[12] The final and longest lived routing of the A began service on September 25, 1939.

Tracks on Fountain were removed from service in 1942, and the line ceased to operate on June 30, 1946.