Allegheny Islands Wilderness is located in the Allegheny National Forest.

7 islands in the Allegheny River, totalling 368 acres, are part of the wilderness. All are alluvial in origin, which means they were formed by water-carried deposits of sand, mud and clay. They are characterized by river bottom forest trees such as willow, sycamore and silver maple. The islands are located between Buckaloons Recreation Area and Tionesta, PA. They are: Crull's Island (96 acres) - home to large old river bottom trees; Thompson's Island (67 acres) - the only Revolutionary War battle in northwestern Pennsylvania occurred here; R. Thompson's Island (30 acres); Courson Island (62 acres) - the island may be viewed from the Tidioute Overlook; King Island (36 acres) - offers good riverine forest with many trees 35-50 inches in diameter; Baker Island (67 acres) - stood in the path of one of the two tornadoes which crossed the Forest on May 31, 1985; No Name Island (10 acres) - comprised of half river-bottom trees and half dense undergrowth.

• Visit Thompson's Island, where the only revolutionary war battle in northwestern Pennsylvania occurred.