Dahlgren, IL -- U.S. village in Illinois Population (2000): 514 Housing Units (2000): 245 Land area (2000): 1.003725 sq. miles (2.599636 sq. km) Water area (2000): 0.000000 sq. miles (0.000000 sq. km) Total area (2000): 1.003725 sq. miles (2.599636 sq. km) FIPS code: 18303 Located within: Illinois (IL), FIPS 17 Location: 38.199117 N, 88.685737 W ZIP Codes (1990): 62828 Note: some ZIP codes may be omitted esp. for suburbs. Headwords: Dahlgren, IL Dahlgren