IRT White Plains Line
The building of the IRT subway into the Bronx provided a fast and inexpensive way to commute into Manhattan and, thus, was pivotal to a massive influx of development in the South Bronx in the early 20th century. The three-track, three-mile elevated line between Brook Avenue and Bronx Park at 181st Street was section #10 of IRT contract #1 and work began on on August 19, 1901. The section was completed a few months before the rest of the IRT and opened in November of 1904 with a connection south of Jackson Avenue to the now-defunct Third Avenue El (NYCSubway.org)