Castle Hill Lighthouse is located on Narragansett Bay in Newport, Rhode Island at the end of the historic Ocean Drive. It is an active navigation aid for vessels entering the East Passage between Conanicut Island and Aquidneck Island. The lighthouse was completed in 1890 on property formerly belonging to the naturalist, oceanographer, and zoologist Alexander Agassiz of Harvard University. Agassiz sold the land to the United States Government for the lighthouse for $1.00.