About of the upper Stanislaus basin is within the Stanislaus National Forest, which provides a wide range of outdoor recreation including fishing, camping, backpacking, horseback riding, mountain biking and snowmobiling. Highway 108 along the South/Middle Forks and Highway 4 along the North Fork, a designated National Scenic Byway, provide access to the forest from both sides of the Sierra Nevada. Part of the Pacific Crest Trail, which crosses Sonora Pass, also runs through the Stanislaus River watershed. The upper Stanislaus also includes parts of two major wilderness areas. The Carson-Iceberg Wilderness is located along the North Fork and Clark Fork (the name "Iceberg" comes from a distinctive granite formation along the Clark Fork). The Emigrant Wilderness, encompassing , encompasses the upper Middle Fork and also borders on Yosemite National Park a short distance to the south.