Which Park Is This? Test your knowledge of Oregon's Parks! Start Quiz This State Heritage Site includes the oldest water-powered grist mill in Oregon. What Park is it? Butte Creek Mill Thompson's Mill Cedar Creek Mill Sumpter Valley Dredge At Which Oregon park can you hike the Trail of 10 Falls?This loop trail has an 800-ft variation in elevation over the course of it's 7.2-mile route, and is a designated National Recreation Trail. Silver Falls State Park Columbia River Gorge National Scenic Area Guy W. Talbot State Park This State Park Campground is located along the shore of Oregon's longest reservoir The Cove Palisades State Park at Lake Billy Chinook Prineville Reservoir State Park Lake Owyhee State Park