Hialeah ( /ˌhaɪəˈliːə/) is a city in Miami-Dade County, Florida, United States. As of the 2010 census, Hialeah has a population of 224,669. Hialeah is the sixth-largest city in the state. It is a principal city of the Miami metropolitan area, which was home to an estimated 6,012,331 people at the 2015 census. It is located west-northwest of Miami, and is the only place in the county, other than Homestead, Florida, to have its own street grid numbered separately from the rest of the county (which is otherwise based on Miami Avenue at Flagler Street in downtown Miami, the county seat).