Glen Cove is a city in Nassau County, New York, United States, on the North Shore of Long Island. As of the United States 2010 Census, the city population was 26,964.Part of the early 20th century Gold Coast of the North Shore, Glen Cove has a diverse population. Of Nassau County's five municipalities, Glen Cove is one of the two municipalities that is a city, rather than a town, the other being Long Beach on the South Shore.The city was also the location of several successful manufacturing facilities in the 20th century.