[3] The line runs from Cotley Junction where it meets the Middleboro Secondary near Weir Village (in Taunton) south to New Bedford[4] along a former New York, New Haven and Hartford Railroad line.

The Fall River Secondary branches off at Myricks Junction.

CSX agreed to sell the Fall River Secondary and New Bedford Secondary for use by the South Coast Rail project, as well as the Grand Junction Branch, the Framingham-to-Worcester section of the Worcester Line, and the South Boston Running Track.

Other parts of the agreement included plans for double-stack freights west of Worcester and the abandonment of Beacon Park Yard.

[7] On June 11, 2010, the state and CSX completed the first phase of the agreement, including the transfer of the South Coast Rail lines to MassDOT; the Massachusetts Coastal Railroad assumed freight rights on the two lines.