Synchronized express and local trains for urban commuter rail systems

A computerized system and method of managing subway trains along a two-track subway line to allow express travel in combination with local service. Express trains catch up to local trains at express stations along the line, and provision is made to allow the express trains to physically or "virtually" pass the local train at those stations. Embodiments in which the express trains physically pass the local train include direct train-to-train transfer facilitated by side-by-side tracks at the express station occupying reduced footprint. In other embodiments, virtual passing is accomplished by changing the type of service provided by trains at express intervals: a local train "transforms" into an express train and vice versa. Embodiments enable passengers to transfer between trains at express stations so that these "relay" passengers can travel faster than any specific train.