60511 -- U.S. ZIP code Municipality (1990): BIG ROCK, Illinois All ZIPs for this municipality (1990): 60511 Population (2000): 1862 Housing Units (2000): 668 Land area (2000): 29.144726 sq. miles (75.484490 sq. km) Water area (2000): 0.000000 sq. miles (0.000000 sq. km) Total area (2000): 29.144726 sq. miles (75.484490 sq. km) Located within: Illinois (IL) Location: 41.755370 N, 88.548650 W