The 79th Street Crosstown Line is a bus line in Manhattan, New York City, running mostly along 79th Street on the Upper West and Upper East Sides of Manhattan. Originally a bus route owned by the private Green Bus Lines, it now comprises the M79 Select Bus Service bus line. The M79 local bus route was identified as a heavily traveled corridor in a 2009 study by the DOT and NYCTA, and in a December 2013 study by the Pratt Center for Community Development of Brooklyn. It was converted to SBS on May 21, 2017.