It was originally built in 1902 and opened in 1903 as a rail link between the Fore River Shipyard at Quincy Point and the New York, New Haven and Hartford Railroad in East Braintree, a length of 2.7 miles (4.3 km).

The Fore River Railroad connects with CSX Transportation in Braintree, via the Greenbush Line of MBTA Commuter Rail.

The Fore River Railroad was originally formed by Thomas A. Watson, telephone pioneer and assistant to Alexander Graham Bell.

Wealthy from his telephone inventions, Watson decided to try his hand at shipbuilding, and purchased land at Quincy Point in Massachusetts where he completed a shipyard in 1900.

However, Watson did not charter his railroad, and therefore could not use eminent domain to purchase all of the necessary land; as a result, he "was forced to pay dearly for one parcel needed for the right of way".

Traffic was modest post-war, until the start of World War II brought increased demand for warships and more business to the shipyard.

[6] While its primary purpose for existing was gone, the Fore River Railroad continued operating to serve a few local industries; these included a soap manufacturer and an oil facility.

Under Quincy Bay Terminal, the railroad began operating over a short segment of the Greenbush Line to connect with Conrail in Braintree.