Locust Valley is a hamlet and census-designated place located in Nassau County, New York. Locust Valley is an unincorporated area of the Town of Oyster Bay. As of the United States 2010 Census, the CDP population was 3,406. The area is commonly identified with its W.A.S.P and "White Shoe" culture surrounding a group of polo and golf clubs, primarily the secretive Piping Rock Club, as well as the equally prestigious Creek Club, in the neighboring incorporated villages of Matinecock and Lattingtown, respectively. The town is also known for Locust Valley lockjaw.Figures ranging from the Duke of Windsor to John Lennon to Franklin D. Roosevelt have spent considerable time in Locust Valley.