The Nantucket Lightship or United States Lightship WLV-612 (Nantucket I) is a lightvessel commissioned in 1950 that became the last lightship decommissioned in United States Coast Guard service. The Nantucket Lightship was launched in 1950 and put into service in 1951 as the San Francisco Lightship, 8.6 miles offshore of the Point Bonita Lighthouse and the Golden Gate where it was in service until 1969. From 1969 to 1971, it served as the Blunts Reef Lightship at Blunt's Freed near the Cape Mendocino Light in Northern California. From 1971 to 1975 it served as the Portland Lightship marking the entrance to Portland, Maine. It was the last lightship to serve as the Portland Lightship in 1975 when it was replaced by a Large Navigational Buoy. The Coast Guard estimated that it would spend $25