supports the underground North–South Rail Link). This would eliminate the need to use multiple rapid transit lines to travel between terminals, but would still require two transfers for Amtrak and commuter rail passengers passing through downtown Boston. Unless grade separated, the link would have to operate at slow speed through very congested downtown traffic. See also Center City Commuter Connection – a similar tunnel opened in Philadelphia in 1984 to connect two previously-separate rail terminals Regional Connector (ca. 2023), will connect 2 light rail lines in downtown Los Angeles Crossrail – a similar project in London, England East Side Access – a commuter rail project in New York City with a high-traffic terminal being built deep under Grand Central Terminal Gateway Program (Northeast Corridor) – a proposed commuter rail project in the New York City area with two tunnels between New Jersey and New York Penn Station Oslo Tunnel – a similar project in Oslo, Norway; opened in 1980 Picc-Vic tunnel – a similar project in Manchester, England; never built Stuttgart 21 – a railway and urban development project in Stuttgart, Germany including some 30 kilometres (19 miles) of tunnels and 25 kilometres (16 miles) of high-speed lines References Proposed Monorail Would Link Boston's North, South Stations North–South Rail Link too expensive, panel says The conservation connection – The Boston Globe William M. Fowler Jr., director of the Massachusetts Historical Society The MASSACHUSETTS SIERRA CLUB: North South Rail Link Further reading External links North South Rail Link - an advocacy website Amtrak MBTA Commuter Rail Passenger rail transportation in Massachusetts Proposed railway lines in Massachusetts Proposed railway tunnels in North America Proposed transportation infrastructure in Massachusetts Proposed tunnels in the United States Rail infrastructure in Massachusetts Transportation in New England Underground commuter rail