Groton is a town located on the Thames River in New London County, Connecticut, United States. The population was 40,115 at the 2010 census.Groton is the home of the Electric Boat Corporation, which is the major contractor for submarine work for the United States Navy. The Naval Submarine Base New London is located in Groton, and the pharmaceutical company Pfizer is also a major employer. Avery Point in Groton is home to a regional campus of the University of Connecticut.