Lying within the national historical reserve but administered by the state, this blufftop park occupies Admiralty Head, where a 19C fort was built as part of a three-fort "Iron Triangle" defense system guarding the entrance to Admiralty Inlet. The fort's substantial gun batteries were completed in 1905 and, though the guns were never fired in actual conflict, the fort was used as a training site during both world wars. In 1956, the US government sold the site to Washington State Parks and Recreation, which has preserved its batteries and two rare 10in "disappearing guns." The Admiralty Head Lighthouse, which operated only briefly in the early 20C, now serves as an interpretive center for the fort's history.