Past its south end at US 1, the roadway of Route 137 continues for another 0.3 miles (0.48 km) to I-95, designated as Special Service Road 493 (SSR 493).

[citation needed] Its southern terminus was located at the intersection of Long Ridge Road (Route 104), Summer and Bedford Streets, also known as "Bull's Head", in Stamford.

[4] In 1962, the Tri-State Transportation Committee proposed expanding Route 137 to be four lanes divided with a median and no access control, from I-95 to the Merritt Parkway.

The route previously ran along Summer Street, but was re-designated to run along Cold Spring Road and Washington Boulevard.

[4] Route 104, which originally extended south into downtown Stamford using Bedford and Summer Street, was cut back to end at its current southern terminus at the same time.

[citation needed] In November 2023, following numerous major crashes along the southern portion of Washington Boulevard, the Connecticut State Department of Transportation floated redesigning part of the route to include cycling infrastructure and additional traffic calming devices.

[6] A Road Safety Audit released by the Connecticut Department of Transportation in November 2023 found that a section of Washington Boulevard running through Downtown Stamford was the site of 547 crashes from January 2017 to December 2021.