'St. Louis County, MO' definitions:

St. Louis -- U.S. County in Missouri

From: Gazetteer 2000
Name :
St. Louis -- U.S. County in Missouri
Population (2000) :
1016315
Housing Units (2000) :
423749
Land area (2000) :
507.805447 sq. miles (1315.210013 sq. km)
Water area (2000) :
15.888700 sq. miles (41.151542 sq. km)
Total area (2000) :
523.694147 sq. miles (1356.361555 sq. km)
Located within :
Missouri (MO), FIPS 29
Location :
38.654152 N, 90.378480 W