What is "prairie du sac"

Population (2000): 3231
Housing Units (2000): 1332
Land area (2000): 1.318276 sq. miles (3.414320 sq. km)
Water area (2000): 0.102628 sq. miles (0.265806 sq. km)
Total area (2000): 1.420904 sq. miles (3.680126 sq. km)
FIPS code: 65100
Located within: Wisconsin (WI), FIPS 55
Location: 43.289833 N, 89.728524 W
ZIP Codes (1990): 53578
Note: some ZIP codes may be omitted esp. for suburbs.
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