Cook Forest State Park in northwestern Pennsylvania preserves one of the state’s finest surviving landscapes of ancient eastern forest along the Clarion River. Once used as hunting ground by the Seneca Nation, the area was settled by John Cook in the 1820s and developed by his family through logging and milling. Its most important history centers on saving the old-growth pines and hemlocks of the Forest Cathedral, a cause championed by Major Israel McCreight beginning in 1910. After state legislation and private fundraising, the Commonwealth acquired the core tract in 1927, making it Pennsylvania’s first state park purchased specifically to preserve a natural landmark.