Railroads travel through the places that people prefer not to think about very much. Because of this, it is possible to get a good sense of how things work--or don't work. Towers of ilium offers the following observations:
-Improvements to infrastructure are nearly always layered on top of, or woven within, existing systems. The results tend not to be visually attractive, but things keep on working.
-Private property that borders on rail routes probably has more volatility in terms of cash value. If there isn't a station close by, it suffers more.
-Room for expansion is desperately limited. Decisions made hundreds of years ago have defined right-of-ways within narrow parameters. The private property adjacent to these routes may have low valuation, but it imposes considerable costs on the entire urban network.