The largest county is Okanagan County, with a total area of 13644 km2 (5315 square miles).
Second is Yakima County at 11168 km2 (4312 square miles).
Third is Chelan County at 7754 km2 (2994 square miles).
According to census.gov, King County, Washington, has the most population at 1,859,284 people in 2007.According to "Washington State" history book: King County with 1,685,600 as of 2000.
According to census.gov, the 2007 ACS population estimate for Pierce County, Washington, is 773,165.
That would be Multnomah county, though smallest in area of the 36 Oregon counties, it is the most populous as its county seat, Portland, is the state's largest city. In 2010, the county had a population of 735,334.
The biggest county in Michigan is Marquette County. It has the largest land area, but only about 67,000 people living there.
According to census.gov, Cumberland County, Maine, has the most population at 275,374 people in 2007.Aroostook County by area and Cumberland County by population..
The largest county by population is King. The largest in size is Okanogan, 5,268 square miles.
Fairfax County with an estimated population of 1,037,065 as of 2009. The county is located in the far northern part of the state and is a suburb of Washington, DC.
A county is an administrative division of a state. As of 2014, the largest county in population in Tennessee is Shelby County.
Hinds County is the county in Mississippi with the largest population. Hinds County includes Jackson, the state capital and the most populous city in the state.
Maricopa county
There are 39 counties in the state of Washington. Based on population the largest counties in Washington are King County, Pierce County, Snohomish County, Spokane County and Clark County.
Colorado's largest county is the city and county of Denver (which is also the largest city in the state) and the 2009 population was 610, 345
Washington.
The largest county in the state of Wyoming is Sweetwater County with a population of 43,806 people. Wyoming's total population is 582,658.
South Dakota is a state. The largest county by size (area) in South Dakota is Meade County. The largest county by population is Minnehaha County which contains the state's largest city, Sioux Falls.
According to census.gov, King County, Washington, has the most population at 1,859,284 people in 2007.According to "Washington State" history book: King County with 1,685,600 as of 2000.
Washington with a population of 6,724,540.