San Juan Island National Historical Park, also known as American and English Camps, San Juan Island, is a U.S. National Historical Park owned and operated by the National Park Service on San Juan Island in the state of Washington. The park is made up of the sites of the British and U.S. Army camps during the Pig War, a boundary dispute over the ownership of the island. The camp sites were designated a National Historic Landmark in 1961, and listed on the National Register of Historic Places in 1966. The park was created by an act of Congress in 1966 and expanded slightly in 2013.

San Juan County is a county in the Salish Sea in the far northwestern corner of the U.S. state of Washington. As of the 2020 census, its population was 17,788. The county seat and only incorporated town is Friday Harbor, on San Juan Island. The county was formed on October 31, 1873, from Whatcom County and is named for the San Juan Islands, which are in turn named for Juan Vicente de Güemes, 2nd Count of Revillagigedo, the Viceroy of New Spain.