The Saugus Branch Railroad was incorporated by the state of Massachusetts in 1848, opening in 1853 as a branch from the Boston & Maine Railroad at Malden (formerly known as Linden, MA) to Lynn, via Saugus, at a distance of 10 miles. While seemingly innocent enough, the SBRR was actually part of a much larger rivalry between its parent company, the B&M, and another railroad in the area, the Eastern Railroad. Each wanted its part of the lucrative passenger market that Boston had to offer. In order for the B&M to capture some of the potential ridership from the Eastern Railroad, they extended the tracks of the SBRR to within close proximity of Eastern's line in Lynn, MA. The Eastern Railroad, seeing a B&M branch line so close to their own, somehow purchased a controlling interest in the SBRR from the B&M in 1855.
The tables had now turned -- the Eastern Railroad now operated the SBRR, but with no physical connection to their own line (and, no less, it still had a connection at Linden with the competition, B&M), they successfully petitioned the state legislature to 1) sever the line's connection with the B&M, 2) extend the "northern" end of the line just a bit more and build a new connection with their own line at Lynn, and 3) extend the "southern" end, formerly connected to the B&M, to the east for another mile or so to connect with their own line again at Everett.
By 1884, the Eastern Railroad fell to the hands of B&M, and the famous war between these two rival railroads came to an end. Not much is known about the Saugus Branch Railroad afterwards. It is believed that the line, along with all other ex-Eastern Railroad lines, were purchased by the MBTA for transit use during the 1970s. The line in its entirety lays abandoned today.
Mike Damico shares some photos of the abandoned line between Adams Avenue and Denver Street in Saugus, MA.