by WorldwideRailfan (Youtube)
I was thinking earlier today about this and I'm sure some people also have. Are all subway lines connected to the commuter rail? I know the green line is connected at Riverside and the red line is connected at Cabot. I also believe the orange line is connected at Wellington but I'm not sure. Anybody know about the blue line? This also brings up the question about if the subway lines are all connected or are they all independent of each other?