Important facts are as follows:
- Line started on November 1, 1905 by the Metropolitan Street Railway Company.
- Line ran on 145th Street from Broadway to Lenox Avenue.
- On August 5, 1912, the Third Avenue Railway Company started to operate the 149th Street Crosstown from Broadway and 145th Street, bridge, 149th Street in the Bronx to Southern Boulevard.
- On April 9, 1915, the Third Avenue Railway Company started operating from Broadway and 145th Street from 181st Street via Broadway, St. Nicholas Avenue, Amsterdam Avenue, and 145th Street and Lenox Avenue.
- On July 11, 1920, New York Railways discontinued the 145th Street Crosstown, but Third Avenue Railway operated streetcars until they were replaced by buses in 1947.
The information shown above comes from the source sited, but it is not clear from the description for the Third Avenue Railway Company if cars ran from Broadway and 145 Street to Lenox and another branch from 181 Street and Broadway to Amsterdam Avenue and 145th Street and across 145th Street to Lenox Avenue. The Broadway and 145th Street description may be a mistake for 181st Street cars.. Also map does not show Bronx trackage.