Nassau County, Kings County, Queens County, and Suffolk County are all counties located on Long Island in New York State. Nassau County is the most populous county in the state, with a population of 1.3 million people. Kings County is the second most populous county, with a population of 2.6 million people. Queens County is the third most populous county, with a population of 2.3 million people. Suffolk County is the fourth most populous county, with a population of 1.5 million people. All four counties are part of the New York metropolitan area and are connected by bridges and tunnels.