I have been working on a personal project to make a to-scale map of the railroads of the tri-state area. The project has two intentions - #1 as a learning experience for me, as I need to study the systems before I can draw them and #2 as a resource for fellow railfans. The project is starting with Metro-North, as that is the railroad I am most familiar with, and will eventually include the entire NJT and LIRR systems, as well as the Amtrak Shoreline and Springfield lines in Connecticut, and some of the freight lines in the area. Although I have heard a number of moral objections to this project by other railfans that are worried that these maps could be used for sinister purposes, I can't imagine a possible way that anybody could use this information to damage or harm the trains or passengers, which they couldn't otherwise do on their own. The point is proved because I am not a railroad employee, and therefore my research comes from publically seen observations, both from riding these lines and aerial photography, and from employee timetables and track charts, which despite being stamped "for employees only" seem to have no trouble being leaked out, both on website postings and ebay sales. The point is, if somebody wanted to use the data on my map for sinister purposes, they could have found this information on their own, and I seriously doubt that not having such easy access to a track map of NYP or GCT would thwart an attack. Nobody needs to know that the engine yard in Grand Central is numbered tracks 90-94 and is located between the leads to tracks 34 and 33 in order to plant an attack there, nor would they even care. They would just walk up one of the platforms or look out the window of a train and see what they need to see.
Anyway, I have completed a map of GCT which has been verified as of 2006 (actually, I was in GCT earlier today verifying some portions of this map), and will do the same for NYP when I get to that portion of the project, but I'm still a bit hasty about posting it on this board until the entire project is completed, since I know that some readers (and possibly moderators) share a completely different view on this subject than I.
In the meantime, this low-res preview
should give the curious parties an idea of the layout of GCT, without giving anything specific away.