Castle Hill Lighthouse is located on Narragansett Bay in Newport, Rhode Island at the end of the historic Ocean Drive and is an active navigation aid for the United States Coast Guard and boaters entering the East Passage between Jamestown, Rhode Island on Conanicut Island, and Newport, Rhode Island on Aquidneck Island. The lighthouse was completed in 1890 on property formerly belonging to the famous naturalist, oceanographer, and zoologist Alexander Agassiz of Harvard University. Agassiz sold land to the United States Government for the lighthouse for $1.00. After the hurricane of 1938, Mrs. Maximillian Agassiz, daughter-in-law of Alexander, sold the rest of the property to J. T. O'Connell, whose descendants are the current owners of the Castle Hill Inn and Resort. Although the lighthouse is not open to the public, the shoreline and clifface where the lighthouse sits is accessible by several footpaths from the Castle Hill Inn. The Castle Hill Lighthouse has also been and still is used as a starting and/or stopping point in numerous regattas. The lighthouse has a red light that flashes about every eight seconds during the night.