Commuter rail between Newbury Port and Swampscott.
Just now back from a very quick trip to Massachusetts. Once there, I
loved being able to take the train between places while visiting
friends. I haven't spent much time in MA and it was nice to sit back see
some of the landscape.
Once upon a time, I took the train across
the country and I highly recommend this to anyone who is able to take
off for a few days. We didn't get a sleeper, just regular seats (which
were huge), and spent tons of time in the observation car, just plain
staring out the window. Also, the train allows you to talk with people
you might otherwise never meet. The trip was fascinating; a true
cross-section of America, both geographically and culturally.
See this great article in The New York Times Magazine about riding the train. How to Spend 47 Hours on a Train and Not Go Crazy.