From over 13,000 feet on the south side of Mt. Lyell, the Merced River gets off to an icy, cold start.  Winding through ancient canyons, carved by glaciers from another age, the river flows through Yosemite National Park down to the Lake McClure Reservoir. Its journey includes snow-covered peaks, alpine and subalpine meadows and clear, fresh water lakes. Pristine and largely unaffected by outside influences, the South Fork of the river still boasts one of the few self-sustaining populations of rainbow, eastern brook and brown trout.