About 4,500 acres, or about 73% of the town's land area, is owned by the National Park Service, which operates the Cape Cod National Seashore, leaving about of land under the town's jurisdiction. To the north lie the "Province Lands", the area of dunes and small ponds extending from Mount Ararat in the east to Race Point in the west, along the Massachusetts Bay shore. The Cape Cod Bay shoreline extends from Race Point to the far west, to Wood End in the south, eastward to Long Point, which in turn points inward towards the town, and provides a natural barrier for Provincetown Harbor. All three points are marked by lighthouses. The town's population center extends along the harbor, south of the Seashore's lands.