Route 23 began its service as an electrified rail and streetcar line between Middle River and downtown Baltimore in 1897 along much of the same route as today. The streetcar operated until 1942, until the line was converted into a rubber-tire bus service. During these years, Route 23 did not serve the west side of town at all. The western portion of today's route was primarily served by the no. 14 streetcar (no relationship to today's Route 14 that operates between Baltimore and Annapolis). Service was also provided through Essex and Middle River on the Back River Trolley.