North–South Rail Link

The North–South Rail Link is a proposed pair of rail tunnels, each about 1.5 miles (2.4 km) long, that would connect North and South Stations in downtown Boston, Massachusetts.

The tunnels would better link Amtrak's various trains into and out of the city, but would mainly benefit the MBTA Commuter Rail by connecting its northern and southern lines. Currently, the Amtrak Downeaster line from Maine has no direct connection to the Northeast Corridor routes south and west. Both Amtrak and the commuter rail lines currently terminate at North and South Stations.

Earlier studies indicate the tunnels would save MBTA more than $67 million in annual operating costs. The tunnels would not be able to handle diesel locomotives and therefore would mandate the electrification of MBTA main lines. This electrification would help Massachusetts and the MBTA reach their greenhouse-gas reduction goals, ensure more reliable service, and obtain quicker train accelerations and significantly shorter travel times. The tunnel would also feature a direct connection to Logan Airport from the commuter rail system via the Blue Line.

From 1872 to 1969, the freight-only Union Freight Railroad provided a direct, street running connection between most of the south-side and north-side railroads, and served local customers and wharves in between.

From 1901 to 1938, the Atlantic Avenue Elevated provided direct passenger service past North and South Stations. The elevated trackage was not connected to any of the conventional railroad tracks.

Public transit connects North Station to South Station only indirectly, requiring two subway lines, either the Green Line and the Red Line, or the Orange Line and the Red Line. Amtrak recommends that passengers with young children or luggage take a taxi between the stations.

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