The Long Island Rail Road, legally known as the Long Island Rail Road Company and often abbreviated as the LIRR, is a commuter rail system in the southeastern part of the U.S. state of New York, stretching from Manhattan to the eastern tip of Suffolk County on Long Island. With an average weekday ridership of 337,800 passengers in 2014, it is the busiest commuter railroad in North America. It is also one of the world's few commuter systems that runs 24 hours a day, 7 days a week, year-round. It is publicly owned by the Metropolitan Transportation Authority, who refer to it as MTA Long Island Rail Road.
The LIRR is one of two commuter rail systems owned by the MTA, the other being the Metro-North Railroad. Established in 1834 and having operated continuously since then, it is the second-oldest US railroad still operating under its original name and charter. There are 124 stations, and more than 700 miles (1,100 km) of track, on its two lines to the two forks of the island and eight major branches, with the passenger railroad system totaling 319 miles (513 km) of route.