Authority took over operations in 1962. In 2010, because of service cuts, the M21 was rerouted from Avenue C to the FDR drive, becoming a river-to-river crosstown line along Houston St. To replace the M21 on Avenue C, the M9, which ran to 14th Street-Union Square via Avenue B and 14th St north of Houston St, was rerouted to Avenue C up to 23rd Street only. In 2013, the M9 was extended to 29th Street at Bellevue Hospital, the original northern terminus of the M21. References External links Streetcar lines in Manhattan M008 Railway lines opened in 1869 1869 establishments in New York (state) 009