New Castle County.
Sussex County.
As of 2021, the population of Delaware County, Pennsylvania, is estimated to be around 566,753 residents.
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New York's largest county by population is Kings County. At the 2010 Census, the population of Kings County was 2,504,700. The second largest county is Queens County with a population of 2,230,722.
Marion County, which encompasses the city of Indianapolis, has the largest population in Indiana.
Sussex County.
SIZE: The largest Minnesota county by size is St. Louis County (6,226 square miles). POPULATION: The largest Minnesota county by population is Hennepin County (population of 1,116,200).
The largest county in Missouri by population is st. Louis
Shelby is the largest county in Tennessee based on both population and on area. As of the 2010 census, Shelby County had a population of 927,644. Davidson County is the second largest county in Tennessee with a population of 569,891.
It is the 45th largest state by population.
Nye County, population 38,180, is the second largest county in the United States!
A county is an administrative division of a state. As of 2014, the largest county in population in Tennessee is Shelby County.