What is "ridge farm"

Population (2000): 912
Housing Units (2000): 388
Land area (2000): 3.127308 sq. miles (8.099691 sq. km)
Water area (2000): 0.000000 sq. miles (0.000000 sq. km)
Total area (2000): 3.127308 sq. miles (8.099691 sq. km)
FIPS code: 63862
Located within: Illinois (IL), FIPS 17
Location: 39.896836 N, 87.652588 W
ZIP Codes (1990): 61870
Note: some ZIP codes may be omitted esp. for suburbs.
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