Setauket-East Setauket , more commonly known as the Setaukets (or that region's core), is a census-designated place (CDP) in Suffolk County, New York, on the North Shore of Long Island. As of the 2010 United States Census, the CDP population was 15,477. The CDP encompasses the hamlets of Setauket (formerly West Setauket) and East Setauket. Founded in 1655, it is the first settlement and namesake, after anglicization, of the Town of Brookhaven.