Harstine Island (Wash.)

Harstine Island (also known simply as Harstine or Hartstene) is an island in Mason County, Washington, United States. The US Census recognizes it as an unincorporated community. The island is located west of Case Inlet in southern Puget Sound, 16 km (9.9 mi) north of Olympia. It has a land area of 48.305 km2 (18.651 sq mi), and had a population of 1,412 as of the 2010 census. Pickering Passage, to the northwest, separates the island from the mainland, while Case Inlet, to the east, separates it from the Key Peninsula. Squaxin Island lies to the southwest, separated by Peale Passage. To the south, Harstine Island is separated from the mainland by Dana Passage. The island is home to Jarrell Cove State Park and Harstine Island State Park.