M15 (New York City bus)

The Second Avenue Railroad opened the line in 1853 and 1854, from Peck Slip on the East River north along Pearl Street, Bowery (shared with the Third Avenue Line), Grand Street, Chrystie Street, and Second Avenue to East Harlem. A short branch was later built along Stuyvesant Street and Astor Place to end at Broadway in NoHo. The Metropolitan Street Railway leased the line in January 1898, and on April 3 the line from Astor Place to Manhattan was electrified. The original line was later electrified to the Bowery, where streetcars used the Third Avenue Line to City Hall, and the line to Peck Slip was abandoned.

Buses were substituted for streetcars by the East Side Omnibus Corporation on June 25, 1933. The New York City Board of Transportation took over operations in 1948, with the New York City Transit Authority (NYCTA) replacing it in 1953.

Limited-stop service began on September 13, 1976, with buses making only 15 stops, spaced every eight blocks, between 126th Street and Houston Street, saving riders up to 23 minutes. Limited-stop service ran every six minutes on weekdays, heading southbound in the morning, between 7:12 and 9:21 a.m., and northbound in the afternoon, between 4:12 and 6:11 p.m.^[6] These buses were identified by signs on the lower right side of the windshield.^[7] As part of the project, new dedicated bus lanes were installed.

On September 7, 1987, a public hearing was held to discuss the NYCTA's plan to reduce the span of weekend evening M15 service to City Hall and Park Row from ending at 12:40 a.m. to ending at 8:10 p.m.. In addition, the hours of weekday service were to be lengthened slightly. The changes were to be made to provide a more uniform service frequency and service pattern.^[8]

On January 13, 1997, 108 more limited-stop trips were added on weekdays.^[9] In June 2002 as part of an outside study, the First/Second Avenues corridor was identified for the implementation of bus rapid transit (BRT) service, due to heavy ridership and slow travel speeds on the corridor.^[10][11] In November 2002, the MTA Board voted to lengthen the span of weekday evening southbound service by one hour to 7:50 p.m., weekday northbound service by 1.5 hours to 9:45 p.m., the span of northbound evening Saturday service by one hour to 8:25 p.m., and the span of northbound Sunday service to 8:10 p.m.. The service increase was expected to result in no change in costs initially. Though the change was initially expected to take effect in March 2003,^[12] it was implemented on April 14, 2003.^[13]

In late 2004, the Metropolitan Transportation Authority (MTA) and the New York City Department of Transportation selected the route as one of the candidates for bus rapid transit service, along with Fordham Road (since implemented), Nostrand Avenue, Merrick Boulevard, and Hylan Boulevard. This evolved into Phase I of the Select Bus Service (SBS) program in 2006.^{[10][14][15][16]} On October 10, 2010, service began on the M15 Select Bus Service, replacing limited stop service.^{[16][17][18][19]} Due to the construction of the Second Avenue Subway, the M15 SBS initially had no stop at 72nd Street, even though that was a major street that had been served by limited-stop buses.^[20] Both the M15 local and M15 SBS were previously assigned to the 126th Street Depot until January 4, 2015.^[21]

The M15 runs between South Ferry in the Financial District and 126th Street in East Harlem. ^[22] Southbound service uses Second Avenue from East 125th to Houston Streets, then uses First Avenue, Madison Street, Water Street and South Ferry. Limited buses made all stops south of Houston Street. ^[23] Prior to the implementation of the M15 SBS, previous M15 Limited stops were eliminated at St Mark's Place and East 72nd Street north of Houston Street. Several stops south of Houston Street were also eliminated.^[24][25]During the daytime and evening hours, local service alternates between Whitehall Street and Pike Street / Cherry Street. During AM Rush Hour, some Select Bus Service trips terminate/originate at Houston St.^[26] Overnight service is provided by local buses only, serving Whitehall Street-South Ferry. Select Bus Service trips terminate at the South Ferry bus loop. By then, the MTA had discontinued service to City Hall due to budget cuts.^[27]

•   Media related to M15 (New York City bus) at Wikimedia Commons
• M15 First/Second Avenues SBS − mta.info
• First Avenue And Second Avenue Select Bus Service − NYCDOT