Fort McKinley, Battery Berry Observation Station, North side of Wood Side Drive approximately 80 feet east of Spring Cove Lane, Great Diamond Island, Portland, Cumberland County, ME

Significance: Fort McKinley attains significance as the largest of Portland Harbor's five military complexes built in the late 19th and early 20th centuries. The fort protected Maine's principal city with one of the most well-defended harbors in the country. Battery Berry Observation Station is one of seven such stations built at Fort McKinley between 1905 and 1909 to control and monitor gun fire from the fort's large batteries.
Survey number: HAER ME-59-B
Building/structure dates: 1905 Initial Construction
Building/structure dates: 1907 Subsequent Work