Last summer I was at a park in Hingham that used to be a weapons station annex for Weymouth Naval Air Station and there were ROWs all over the place. Also, there used to be a NIKE site there during the Cold War. It seems to me that I read someplace while researching the annex that it, along with Weymouth NAS, were served by the Old Colony (PRR). The rail line was used to shuttle munitions to and from the air station.
Now that I think of it, that may have been the Greenbush Line that served the NAS. See the MBTA Project Plan for the new Greenbush line...
http://www.mbta.com/projects_underway/g ... sp#project