Regional commuter rail, heavy rail “Metro” services, and newer “light rail” systems have the greatest potential community potential. A well-designed rail system can span an entire county, and be designed with the entire region in mind. The New York system services the city proper, the five boroughs, and the surrounding tri- state area. Metros can create competitive megaregions, allowing residents to commute longer distances. Most importantly, Metros and light-rail systems are connected to other transit modes, establishing better connectivity with the rest of the country.
Commuter rail is used primarily by commuters, servicing few areas between stations. Metros have closer stops. Light-rail systems are not as fast but are considerably less costly. Implementing a well-thought-out Metro system is a high priority for populous regions, but cannot be the only method of public transit in a comprehensive system.