The Cape Ann Light Station was established by the Commonwealth of Massachusetts. Their authority and funding provided for building this twin-light station on the northeast side of the fifty acre Thacher's Island, Rockport, MA. The original twin rubble masonry lighthouses were built in 1771 and stood 298 yards apart. The north tower was only 39 feet high and the south tower 35 feet high. They were oriented in a northeast-southwest alignment.
Both of the aforementioned lights operated until 1861 when they were replaced by the pair of 124-foot high cut granite structures pictured below. Each tower is 30 feet in diameter at the base, 18 feet at the top, and the lantern rooms equipped with first-order Fresnel lenses. Originally, both towers displayed fixed white lights. When the beacon in the north tower was extinguished in 1932, as an efficiency move, the south tower light was changed to a more intense flashing white beam. The light was later changed to red and continues to be operated by the U. S. Coast Guard as an official aid to navigation. Cape Ann Light Station is the only twin light in official operation in the U.S.
In 1980, Thacher's Island became the property of the Town of Rockport, the same year the south light was automated. At the time of my 2001 visit, the property was managed by the Thacher4's Island Association in cooperation with the U.S. Fish and Wildlife Service. One of its notable achievements was the successful restoration of the long-neglected north tower, which was relighted in 1989 as a private aid to navigation. That same year and for the next several years, the Association operated a launch for island visitors until a winter storm in 1995 destroyed the landing ramp. The group hoped to renew the trips once the landing area was restored, and most likely have done so before the time of this posting.