The Lewis and Clark National Historical Park, located in the vicinity of the mouth of the Columbia River, commemorates the Lewis and Clark Expedition. Administration of the park, which includes both federal and state lands, is a cooperative effort of the National Park Service and the states of Oregon and Washington. The National Historical Park 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 park features a replica of the fort and a nearby visitor center. Also included in the park are several sites on the north bank of the river in Washington and other sites in Oregon.
Wikipedia https://en.wikipedia.org/wiki/Ecola_State_Park
Official website http://www.nps.gov/lewi/planyourvisit/ecola.htm
Coordinates 45°56'29.575" N -123°58'25.587" E