The B&P was completed in 1835 and began operating the steamer Lexington between Providence and New York, adding the Massachusetts in 1836.

On November 17, 1837 the line opened between Stonington and a pier at South Providence, about 1 mile downriver from the city center.

The terminal for steamboats connecting to the Long Island Rail Road was moved to Groton, on the east shore of the Thames River.

In 1864, the NYP&B purchased the NHNL&S line east of Groton; the remainder was leased by the New York and New Haven Railroad in 1870.

[6] In 1889 a bridge was built across the Thames River, connecting the two segments and completing the all-rail Shore Line.

Penn Central went bankrupt in June 1970, and was merged into Conrail in 1976, but the old NYP&B main line was sold to Amtrak (in Connecticut) and the state of Rhode Island.

It now hosts Amtrak's Acela Express high-speed trains and Northeast Regional conventional service.