In May 1852, the New London & Stonington was chartered to build a railroad from Stonington to Groton, completing the last major section of the "Shore Line" rail link from Boston to New York City.

In November 1859 the line was leased to the New York, Providence and Boston Railroad; through passenger service began December 12, 1859, with night trains first running August 19, 1861 and sleeping cars November 11.

When the Clamdigger commuter train was revived for the last time on January 8, 1978, Amtrak added commuter-based flag stops at Groton, Clinton, Madison, Stony Creek, and Branford, in addition to the mainline stations it had served since 1976.

In 2022, the Connecticut Department of Transportation began studying a potential extension of Shore Line East service from New London to Westerly, including a new Groton station.

[3] Media related to Groton station (Connecticut) at Wikimedia Commons