Allegheny National Forest — Old-Growth Pines, the Sky Walk & the Reservoir

Three days in the deep forest of northwestern Pennsylvania, tracing the Allegheny National Forest and its surrounding state parks from ancient pines on the Clarion River to a ruined railroad viaduct turned skywalk and the great Kinzua Reservoir. Day one is spent among the towering old-growth white pines and hemlocks of Cook Forest State Park — the 'Forest Cathedral,' some trees over 300 years old — with the Clarion River sliding quietly below. Day two crosses the forest to Kinzua Bridge State Park, where the wreckage of a once-record-setting railroad viaduct, toppled by a 2003 tornado, has been reborn as the vertigo-inducing Kinzua Sky Walk out over the gorge, followed by the shores of the vast Allegheny Reservoir. Day three closes at Hearts Content, one of the East's finest surviving stands of virgin forest, and the riverside town of Warren before the drive home. Overnights in the Clarion and Warren areas bridge the days. It is a woods-deep weekend of moderate forest hiking, big trees, big water, and one unforgettable walk out over a gorge.