AirTrain Newark is a 3-mile monorail system connecting the terminals at Newark Liberty International Airport and trains at Newark Liberty International Airport Station on the Northeast Corridor, where transfers are possible to Amtrak and New Jersey Transit's Northeast Corridor Line and North Jersey Coast LineAs of 2015, the system is slated for replacement.HistoryThe monorail opened in 1996 and initially served only as an airport circulator, a service which allows passengers to transfer between airport terminals or concourses. The monorail track was refurbished and extended to the NEC, with construction beginning in 1997. The system reopened for service on October 21, 2000. When first opened in 1996 a fleet of 12 six-car Bombardier trains ran on the network. It has expanded to 18 six-car trains.The contract to build the system was awarded to Von Roll AG, but the project was finished by Adtranz, who acquired Von Roll's monorail division while the system was being built. Adtranz was later acquired by Bombardier Transportation, who continues to operate the AirTrain under contract to the Port Authority of New York and New Jersey, the operator of the airport.