61448 -- U.S. ZIP code Municipality (1990): KNOXVILLE, Illinois All ZIPs for this municipality (1990): 61448 Population (2000): 4176 Housing Units (2000): 1648 Land area (2000): 34.962719 sq. miles (90.553022 sq. km) Water area (2000): 0.024351 sq. miles (0.063068 sq. km) Total area (2000): 34.987070 sq. miles (90.616090 sq. km) Located within: Illinois (IL) Location: 40.910079 N, 90.271711 W