Three of the four mainline tracks are occupied in Elizabeth. North and southbound NJ Transit trains are on Tracks 1 and 4, while an Amtrak AEM-7 is pushing an eastbound Keystone Service train. Note three locomotive models... NJT Bombardier ALP45DP, Amtrak ASEA AEM-7, and a NJ Transit Alstom ALP46. The Northeast Corridor remains an interesting railroad line for different types of locomotives and passenger cars.