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Former US Army Coast Artillery Fort in Oahu, Hawaii
Fort Armstrong is located at Honolulu, Oahu and was built on fill over Ku-akau-kukui reef in 1907 to protect Honolulu harbor. It had one named Battery, and was spread over 64 Acres.
Battery Tiernon with two pedestal mounted 3-inch M1903 guns from 1911 to 1943.
The original garrison was the 1st Coast artillery Company followed by the 104th Mine Co. operating the harbor mines. Also stationed there was the 185th Coast Artillery Company. Fort Armstrong continued under the occupation of the Coast Artillery until September 15, 1922, when the Coast Artillery Headquarters moved to Fort De Russy. It was abandoned by the U.S. Army by 1950 and is now part of a container port facility.