The New York City Subway is a rapid transit system that is in New York City, United States. It is run by the Metropolitan Transportation Authority (MTA). It is one of the biggest rapid transit systems in the world, with 472 stations. It has 245 miles (or 394 km) of routes on 691 miles (or 1112 km) of track. The New York City Subway almost never closes; the trains run 24 hours a day, 7 days a week, all year. The system has only closed three times.