The Groton Bridge Co. was an American firm.The company was founded in 1877 as Groton Iron Bridge Company, by merger of two firms. It was reorganized and became the Groton Bridge and Manufacturing Company in 1887. It was purchased by the American Bridge Company in 1899 but was separated in 1902 as Groton Bridge Co. and survived under that name until the 1920s.A number of its works are listed on the U.S.