Willie Keil's Grave State Park Heritage Site preserves the burial place of Willie Keil, a Missouri boy who died of malaria in 1855 just before his family's religious community left for the Pacific Northwest. His father, Dr. William Keil, continued the migration by carrying Willie's body in a lead-lined tin coffin filled with whiskey across the overland route, a journey that helped give Willie the nickname "Pickled Pioneer." The wagon train reached the Menlo area, where Willie was buried on December 26, 1855. Though the settlement later shifted elsewhere, the tiny site endures because of this unusual migration and burial story, one of the Pacific Northwest's most distinctive pioneer accounts.