North Haven [New Haven County] Connecticut was named in 1739 and incorporated from New Haven in 1786.Area, 21.1 sq. miles. Population, est., 22,148. Voting districts, 5. Principal industries, manufacture of aircraft components, paper boxes, miscellaneous non-metallic mineral products, cutlery, tools and general hardware, industrial chemical, miscellaneous wood products, structural clay products, fertilizers, machinery, professional and services equipment, plumbing and heating, manufacture of firearms, commercial printing, sporting goods, electrical and electronic cable and parts, printed circuit boards, aluminum strip mill, steel fabrication, food distribution, die casting, ceramic products, milt and products, scrap reduction.North Haven is considered a part of the New Haven Metro Area.