Cold Spring Harbor is a hamlet and census-designated place (CDP) in the town of Huntington, Suffolk County, New York, on the North Shore of Long Island. As of the 2010 United States Census, the CDP population was 5,070.
Cold Spring Harbor was named after the naturally cold freshwater springs that flow in the area. Its economy mainly tied to milling and port activities, it rose in prominence as a whaling community in the mid-nineteenth century. After the decline of whaling in the 1860s, it became a resort town with several hotels. In the 20th century it became known as the site of Cold Spring Harbor Laboratory, although the laboratory itself is located in the adjacent village of Laurel Hollow in Nassau County, which was called Cold Spring before incorporation.
Today it is primarily a bedroom community of New York City, with a small central business area running along Route 25A, and is home to many educational and cultural organizations: the Cold Spring Harbor Whaling Museum, the Cold Spring Harbor Fish Hatchery and Aquarium, Dolan DNA Learning Center, the Uplands Farm Sanctuary (home of The Nature Conservancy's Long Island chapter), and a museum exhibition gallery run by Preservation Long Island.
Cold Spring Harbor is located at 40°52′N 73°27′W (40.863, -73.443).
According to the United States Census Bureau, the CDP has a total area of 3.9 square miles (10 km2), of which 3.7 square miles (9.6 km2) is land and 0.2 square miles (0.52 km2), or 4.86%, is water.
As of the census of 2000, there were 4,975 people, 1,753 households, and 1,416 families residing in the CDP. The population density was 1,336.3 per square mile (516.4/km2). There were 1,790 housing units at an average density of 480.8/sq mi (185.8/km2). The racial makeup of the CDP was 97.03% White, 0.42% African American, 0.02% Native American, 1.31% Asian, 0.24% from other races, and 0.98% from two or more races.