Cape Fanshaw is a low wooded point at the junction of Stephens Passage and Frederick Sound, about 83 miles (134 km) south of Juneau and 68 miles (110 km) east-northeast of Sitka, Alaska. Cape Fanshaw Light is at the point on a skeleton tower with daymarks 33 feet (10 m) above the water. The cape was named by Captain George Vancouver of the Royal Navy in 1794 after it was discovered by Lieutenant J. Whidbey.
Cape Fanshaw was used as an astronomical triangulation station for mapping in the 18th and 19th centuries. The station has a known coordinate and elevation based on precise measurements of navigational stars. A series of these stations were trigonometrically grouped together to form a network or grid. Positions of land boundaries could then be accurately located by the network. Today this has been largely supplanted by the Global Positioning System. In 1907, President Theodore Roosevelt issued an executive order that set aside the Cape Fanshaw Astronomical Station as a military reservation, and today the cape is used by the U.S. Coast Guard for a radio transmitter and by the Federal Aviation Administration for a camera array.
In most of the U.S. and Canada, a network of very high-frequency radio transmitters is used throughout the coastal areas to carry radio signals and messages to and from ships and to monitor emergency broadcasts. Although western and northern Alaska has no coverage, southeast Alaska has an operational network including a radio repeater at Cape Fanshaw. Read more here and here. Explore more of Cape Fanshaw here: