Access to The City of Warrenton - Fort Stevens State Park West of highway. West to Fort Stevens State Park. Fort Stevens was the primary military defense installation in the three fort Harbor Defense System at the mouth of the Columbia River (Forts Canby and Columbia in Washington were the other two). The fort served for 84 years, beginning with the Civil War and closing at the end of World War II. Fort Stevens State Park Campground. Camping; The park has 174 full hookups, 303 electrical, 42 tent (maximum site 50 feet); 15 yurts; group tent (4 areas); hiker/biker camping -- Start / Finish ofU.S. #30 Road Map Highway Travel Guide. -e