The Lewis and Clark National and State Historical Parks, in the vicinity of the mouth of the Columbia River, commemorate the Lewis and Clark Expedition. Administration of the parks is a cooperative effort of the United States National Park Service and the states of Oregon and Washington, and was dedicated on November 12, 2004. After reaching the Pacific Ocean, the Corps of Discovery camped at Fort Clatsop in the winter of 1805–1806. The parks also preserve several landing sites on the north bank of the river in Washington, and other sites in Oregon.