The Tuolumne River is one of the major rivers draining the western slopes of the Sierra Nevada Mountains of California. The Tuolumne, or “T” as it is known among whitewater aficionados, is “The Champagne of Whitewater,” "The King of Sierra Rivers," and certainly the finest whitewater river in the state. The headwaters of the Tuolumne River originate at 13,000 feet in Yosemite National Park in the Sierra Nevada Mountains. The river runs in a wavy line from east to west, and as it gathers strength through its tributaries, the Tuolumne carves out canyons that provide 27 miles of world-class whitewater for rafters and kayakers. On its course, the river meanders through Tuolumne Meadows and travels toward the west, filling Hetch Hetchy Reservoir. As it runs west, its course deepens markedly as it drops over the first of a string of many waterfalls. Then it tumbles west and out of Yosemite. The Glen Aulin, a beautiful valley, lies below the confluence of Cold Canyon, Conness Creek, and the Tuolumne River. To the northwest of Glen Aulin are two spectacular waterfalls - LeConte Falls and Waterwheel Falls - both known for the "waterwheel" phenomenon. From this point, the Tuolumne enters the Grand Canyon of the Tuolumne – a deep, roughly V-shaped gorge. Below this canyon is the most spectacular part of the Tuolumne's course – the Hetch Hetchy Valley. At the bottom of this valley stands O'Shaughnessy Dam that causes the entire valley to be flooded. Below the dam, the river flows through the Stanislaus National Forest, within which it is joined by Cherry Creek, the South Fork of the Tuolumne River, and the Middle Fork of the Tuolumne River. The towns and cities along the Tuolumne are La Grange, Waterford, Hughson, Empire, Ceres, and Modesto. The Modesto Airport lies next to the river. The Tuolumne watershed supports many species of wildlife, including bald eagles, spotted owls, prairie falcons, and a healthy wild trout fishery. In addition to providing excellent wildlife habitat and recreational facilities, the Tuolumne River has been extensively developed to deliver water and electricity to San Francisco and other Bay Area cities. The river also provides water for farmers in the Central Valley. The Tuolumne offers many rafting, kayaking, hiking, fishing, wildlife viewing, and camping opportunities. The river features technical Class IV and V rapids with names like Nemesis, Thread-the-Needle, and Pinball. The staircase rapids, chutes, and pools by the score make the Tuolumne the ultimate river adventure. The best time to float the Tuolumne River is usually May through September.