Directions:  A 36-mile loop trail traverses the east and west sides of the Oil Creek gorge. Access to the trail is available from several locations, and shorter hikes of 5-mile loops are available. For the more energetic hiking birder, two overnight backpack shelter areas are present. A fee is charged for their use, and reservations are needed. All parts of the trail are good birding sites as the trail covers similar habitat with oak ridgetop and hemlock ravines. Stop at the park office at Petroleum Centre for trail maps and more information. Dark-eyed Junco are present year-round. Black-throated Blue, Hooded, and Black-throated Green warblers plus several vireos are nesters. Louisiana Waterthrush are found along the numerous small ravines, and evening singing of Wood and Hermit thrushes and Veery are enjoyed. Ruffed Grouse and Wild Turkey are seldom missed on any outing. Scarlet Tanager and Rose-breasted Grosbeak occupy the deciduous forests. The trail includes a lot of up and down walking, but much is along old roadbeds. A good hiking boot is recommended plus a water supply for any summer outing.