In this beautiful capture by Nicholas Tonelli, we see the Pine Creek Gorge in Pennsylvania, a 47-mile (76 km) gorge carved by Pine Creek in Pennsylvania. It sits in about 160,000 acres (650 km2) of the Tioga State Forest. Its deepest point is 1,450 feet (440 m) at Waterville. [Source]

Pine Creek Gorge is a product of the last ice age. It flowed northeasterly until about 20,000 years ago, when the receding Laurentide Continental Glacier dammed it with rocks, soil, and other debris. Glacial meltwater formed a lake near the present town of Ansonia, and when it overflowed the debris dam, the creek flooded to the south. Ultimately, it carved a deep channel on its way south to the West Branch Susquehanna River. [Source]