With the surge in automobile use by the 1920s, north-south thoroughfares had grown congested. The Skokie Highway (U.S. 41) was completed in 1937, linking Lake Forest more closely with Chicago by car.

According to the Chicago Tribune in 1936, “when completed [the Skokie Highway] is believe to be the longest super-highway in the nation of four lanes or more in width and also will be the longest continuous section of divided pavement.” The $9 million highway featured modern traffic actuated stop-and-go signals, and a one-mile demonstration section was illuminated with sodium vapor lights for night driving.

This four-lane, divided Skokie Highway created an imposing physical barrier, one that people 90 years later use to demarcate east Lake Forest from west Lake Forest in their minds.