At Felicitas Publica, some articles about changes to the MBTA subway system in Boston over the last 40 years:
- 1967 system map
- Blue Line
- Orange Line
- Red Line
- Green line:
The New England Transportation Site has some historical system maps, as well. And the Wikipedia entry on the T looks jam-packed with information as well.
The Images of America series of books (which I enjoy a lot) has a couple of volumes on urban rail lines in Boston: Boston in Motion (I think I might own this one), Trolleys Under the Hub and Boston’s Blue Line.
I didn’t even know there were informational web sites about the T. Another way to spend a rainy morning.