Nassau County is a county in the U.S. state of New York. At the 2010 U.S. census, Nassau County’s population was 1,339,532, estimated to have increased to 1,356,924 in 2019. The county seat is Mineola and the largest town is Hempstead. Nassau County is situated on western Long Island, bordering New York City’s borough of Queens to the west, and Suffolk County to the east. It is the most densely populated and second-most populous county in New York State outside of New York City, with which it maintains extensive rail and highway connectivity, and is considered one of the central counties within the New York metropolitan area. Nassau County contains two cities, three towns, 64 incorporated villages, and more than 60 unincorporated hamlets. Full HD.