'Jefferson County, CO' definitions:

Jefferson -- U.S. County in Colorado

From: Gazetteer 2000
Name :
Jefferson -- U.S. County in Colorado
Population (2000) :
527056
Housing Units (2000) :
212488
Land area (2000) :
772.093977 sq. miles (1999.714135 sq. km)
Water area (2000) :
5.967159 sq. miles (15.454869 sq. km)
Total area (2000) :
778.061136 sq. miles (2015.169004 sq. km)
Located within :
Colorado (CO), FIPS 08
Location :
39.727160 N, 105.142196 W