Located just south of the Allegheny National Forest, the park is a heavily wooded area of rolling hills and mountains along the Clarion River in northwestern Pennsylvania.

Seneca Rock is still named after the first inhabitants, and the Paramount Pictures' film "Unconquered" was shot here in 1946 by Cecil B. DeMille and starring Gary Cooper and Paulette Goddard.

He arrived in 1826 to determine the feasibility of building an east-to-west canal along the Clarion River for the Commonwealth of Pennsylvania.

[6] At the mouth of Tom's Run, now adjacent to the park office, John built his one-story cabin and the first of many water-driven sawmills.

Andrew's industry expanded, and he built the original Cook Forest Inn for his woodsmen's living quarters.

[7] Cook Forest is the most important tract of virgin timberland to be found in Pennsylvania, and is without rival for size East of the Rockies.

Cook would comment, as he led the way into the silent ‘temple of the gods’, and then listen to the exclamations of astonishment that were sure to come from those who followed along the fern-bound path in this fairyland.

In 1910, McCreight and others formed the Pennsylvania Conservation Association[9] and successfully lobbied the legislature to consider Cook Forest for state park purposes.

For sixteen years a series of unsuccessful legislative bills were introduced for the state to acquire Cook Forest.

[10] Early pioneers with the Cook Forest Association were Major Israel McCreight, Theo Wilson and John Nicholson.

The Association, endorsed by national natural resource groups and Governor Gifford Pinchot, raised $200,000.

[6] On April 14, 1927, a bill was signed by Governor John Stuchell Fisher appropriating $450,000 on condition that the Cook Forest Association raise the remaining $200,000 to purchase the 6,055 acres.

Money from the Association helped the Commonwealth purchase 6,055 acres (2,450 ha) from A. Cook Sons Company in 1927 for $640,000.

In addition, on rare occasions, the top spotting area will be opened by a guide to allow visitors a closer look.

They were built by the Civilian Conservation Corps as part of Camp SP-2, which operated in the park from October 1933 to September 1935.

The Baker Trail runs from Freeport, in southern Armstrong County, to the Allegheny National Forest.

The Bicycle Route is 11.5 miles (18.5 km) long and follows lightly traveled roads within the park and Heffern Run Trail.

Several stables dot the area and are open to the public most of the year; these include Silver Stallion, Pine Crest, and the Cook Forest Scenic Trailride, Dude Ranch, and Campground.

The Department of Conservation and Natural Resources and the Pennsylvania Game Commission rules and regulations apply.

A special fishing pond stocked with trout is by the park office and is available for use by children 12 and younger and people with a disability.

Through hands-on activities, guided walks and evening programs, participants gain appreciation, understanding and develop a sense of stewardship toward natural and cultural resources.

The park has an environmental learning center in the Log Cabin Inn at the Main Picnic Area.

The Verna Leith Sawmill Theater seats 180 people and presents plays, musicals and other entertainment throughout the summer season.