Abstract: Provided are systems, methods, and computer-program products for tracking and locating shipping containers in rail car unloading operations in a railway switchyard using a rail mounted gantry crane. The systems, methods, and computer program products configured to establish the position of shipping containers loaded on rail cars within a rail yard. The position of the shipping containers can be conveyed in terms of relative or absolute coordinates. The systems, methods, and computer program products can use a variety of inputs, rules, and calculations to establish the final resting places of containers mounted on rail cars. The position information may be used to provide various functionality, including creating a log or record of the location of containers or to guide rail mounted gantry (RMG) cranes to unload and work the train(s) of interest.