North–South Rail Link
| North–South Rail Link | |
|---|---|
South Station in Boston in August 2012 | |
| Overview | |
| Status | Proposed |
| Owner | MBTA |
| Locale | Boston, Massachusetts, U.S. |
| Termini | |
| Stations | 2 or 3 proposed |
| Service | |
| Type | Commuter Rail |
| Operator(s) | MBTA |
| Technical | |
| Line length | 5 miles (8.0 km): 68 |
| Number of tracks | 2 or 4 |
| Track gauge | 4 ft 8+1⁄2 in (1,435 mm) standard gauge |
| Electrification | Yes |
The North–South Rail Link (NSRL) is a proposed rail tunnel, or pair of tunnels, that would connect North Station and South Station in downtown Boston, Massachusetts, linking rail networks that serve the city's northern suburbs, New Hampshire, and Maine with the rest of the country. The project would build new underground stations near the existing stations, connect them with about 1.5 miles (2.4 km) of tunnels, and add other tunnels to link up with existing surface tracks.
The NSRL would connect Amtrak and MBTA Commuter Rail lines that terminate either at North or South Station. For MBTA, it would link northern lines to South Station, Back Bay Station, and lines beyond Back Bay, including the Framingham/Worcester Line and the Northeast Corridor; one option under consideration would also link to commuter lines to the south. The project would also link Amtrak's various trains into and out of the city; for example, the Downeaster line from Maine currently has no direct connection with Northeast Corridor trains to New York City and beyond.
In 2017, a Harvard Kennedy School study estimated the cost of the NSRL at $4 to $6 billion (in 2025 dollars), based on Federal Transit Administration data and an analysis of comparable tunnel projects around the world. A 2018 MassDOT study looked at four options with estimated costs ranging from $12 billion to $22 billion (in 2028 dollars).
As of 2025, the North-South Rail Link has not been pursued and is not in active development, though advocates call for updated studies.