Gurnet Light (Plymouth Light Station) as it currently stands today.

Gurnet Light – also known as Plymouth Light – is located 3.8 nautical miles Northeast of Plymouth, Massachusetts. It, along with a Keeper’s cottage and Fort Andrew, make up what is called Plymouth Light Station. (Coordinates: 42.0037° N, 70.6006° W)


(Source US Coast Guard Light List _V1_2019 Page 111)

Height: 39 feet, 102 feet above water

Construction: Wood

Lens: Plastic optical system

Color: White, red sector covers Mary Ann Rocks

Characteristics: Group flashing three (3) flashes every 30 seconds

Range: White = 17 nautical miles; Red = 15 nautical miles

Fog Signal: Two (2) blasts every 15 seconds (3 second blasts). Radio activated (via MRASS) and lasts 60 minutes.


  • Gurnet Light was first built in 1768,  with two lights on the property of John and Hannah Thomas, who also became the first lighthouse keepers.
  • In 1776 Hannah Thomas became the first female light house keeper after her husband, Brigadier General John Thomas, went off to fight in the Revolutionary War.
  • In 1776 the British Frigate Niger fired on a company of militia after they fired on one of her boats. In the exchange, it is possible that the lighthouse was hit.
  •  In 1790 the state turned the lighthouse over to the federal government, who appointed John Thomas, Jr. Keeper.
  • The lighthouse burned in 1801 and the government then rebuilt it as twin towers.
  •  In 1842 the crumbling towers were replaced with two white octagonal pyramidal towers. The north light was 110 feet above sea level, and the south tower 102 feet. However, the lights were too close together and often were seen as a merged single beam of light.
  • In 1871 a fourth-order fresnel lens was installed, greatly increasing the strength of the lights.
  • In 1914 the Cape Cod Canal opened, giving new importance to the Gurnet as a navigational aid.
  • In 1924 the Bureau of Lighthouses discontinued one of the twin lights as it phased out multiple lights. The remaining light still stands.
  • On March 8, 1977, the Plymouth Light Station was officially listed on the National Register of Historic Places.
  • In 1998 the Coast Guard moved the lighthouse back from the eroding 45-foot cliff. It was standing only 50 feet from the edge when it was placed on rollers and moved by tracks 140 feet from its previous site. It now sits on the property of Fort Andrew at Gurnet Point.
  • In 1999 the Coast Guard gave Project Gurnet & Bug Lights, Inc. the first of many 5-year licenses allowing us to restore, preserve, and maintain Gurnet Light.