Two Harbors Lighthouse

Oct. 22, 2019

Two Harbors Lighthouse, Agate Bay, Lake Superior, Minnesota

Built in 1892.


Location: Overlooking Lake Superior’s Agate Bay, Two Harbors, Minnesota
Historic Tower:
Station established: 1892
Year light first lit: 1892
Operational? Yes
Automated? Yes, 1980
Foundation Materials: Stone
Construction Materials: Red brick
Tower Shape: Square (twelve feet squared)
Markings/Pattern: Red dome and ventilator ball on roof of white lantern
Relationship to other structure: Keeper’s house attached
Tower height: 49 feet
Original lens: Fourth Order Fresnel was installed in 1892
Present Optic: DCB-224 Aerobeacon installed in 1969 is visible an average of 17 miles.
Light Pattern: .4 seconds of light, 4.6 seconds of dark, .4 seconds of light, 14.6 seconds of dark. 20 second light pattern repeated three times a minute continuously and automated from a station in Duluth.
Height of Focal Plane: 78 feet above the lake surface.

Historical Information:

  • Oldest operating lighthouse in the State of Minnesota.
  •  Construction began in 1891 and was completed in 1892 to help provide safe passage into Agate Bay Harbor.
  •  Six structures on the station include: the lighthouse tower with attached two-story Keeper’s Quarters, wooden fog horn signal building (1892), Skiffhouse, red brick oil house, wooden Assistant Keepers Quarters (1892), and a wood garage (1936).
  •  Original lens on display at Inland Seas Museum, Vermillion, Ohio.
  •  The original light source was a flame supplied by oil.
  •  A narrow staircase of 40 steps winds up through four tower levels to the lantern. The fourth level has porthole style windows in the watchroom.
  •  Six sides of the octagonal lantern are glazed and two are closed in so the light shines in a 270-degree arc.
  •  The original light had an oil and wick lamp. It displayed a fixed red light. Later a kerosene lamp was used and it was changed to a flashing light. Weighted chains kept the lens rotating to create a flash pattern.
  •  The light was first lit by electricity in 1921.
  •  In 1941 a Radio Beacon distance finding system was installed.
  •  In 1969 the Fresnel lens was replaced with a 24” aerobeacon with two 1000-watt bulbs, which is in current use.
  •  The wood framed fog signal building was covered with iron. It had duplicate 10-inch steam whistles. The fog horn was discontinued in 1973.
  •  U.S. Coast Guard members continued to use the keeper’s house until 1987.
  •  The light station was decommissioned in 1982 but the light is still in use.
  •  Light Station is a current aid to navigation, museum, and a bed and breakfast inn.
  •  The Lake County Historical Society assumed responsibility for the operation of the light from the U.S. Coast Guard in 2001.
  •  The Light Station is open to the public.
  •  The Light Station is listed on the National Register of Historic Places in 1984. Reference #84001483.
  •  The Lake County Historical Society received a grant in 2010 from the Minnesota Department of Natural Resources’ Lake Superior Coastal Program for new exhibits at the Light Station. History of the light station is featured in the Frontenac Pilot House added by the historical society as museum space.


Charles Lederle (1892-1910), Otto Redman (1910-1913), Lee Benton (1913-1915), Alexander McLean (1919-1931), Lawrence Pederson (1931-1940).

Researched and written by Ed Shaw, a volunteer through the Chesapeake Chapter of the U.S. Lighthouse Society.