Right... but that would mean that what you are querying google for doesn't change. The coordinates of the trains would even only be along their route. Once yo

Right... but that would mean that what you are querying google for doesn't change. The coordinates of the trains would even only be along their route. Once you have done a reverse lookup on enough points along the route, you should have a pretty dense idea of where the neighborhoods change, right? I am not sure if I'm missing some big, but it really seems like there wouldn't be an ongoing need for querying google's APIs in this case. Finding the boundaries of the neighborhoods and especially labeling stops should be easy enough to do if it would save so much money.