its first subway line opened, the IRT acquired the Manhattan Railway Company by lease, gaining a monopoly on rapid transit in Manhattan. The IRT coordinated some services between what became its subway and elevated divisions, but all the lines of the former Manhattan elevateds have since been dismantled.

In 1913, as a result of massive expansion in the city, the IRT signed the Dual Contracts with Brooklyn Rapid Transit (BRT) in order to expand