The oldest section is from northwestern Taunton into downtown Taunton, opened in April 1836 as part of the Mansfield-Taunton Taunton Branch Railroad - one of the first railroad lines in New England. The New Bedford and Taunton Railroad completed an extension from Taunton south to New Bedford in 1840, including the current Middleboro Subdivision southeast of downtown Taunton.
The oldest section begins in northwestern Taunton and extends into downtown Taunton, opening in April 1836 as part of the Mansfield-Taunton Taunton Branch Railroad - one of the earliest railroad lines in New England. The New Bedford and Taunton Railroad later extended from Taunton south to New Bedford in 1840, incorporating the current Middleboro Subdivision southeast of downtown Taunton.