The northern portion of the present Route 27 is nearly identical to the No. 25 streetcar line that operated during Baltimore's streetcar era. The Hampden line in Baltimore was the first electric streetcar that operated in the United States.
The northern part of present Route 27 closely resembles the No. 25 streetcar line that ran during Baltimore's streetcar period. The Hampden line in Baltimore was the initial electric streetcar service in the United States.