The Kern River originates in the Sierras near Mount Whitney and winds its way southward through Sequoia National Park, Golden Trout Wilderness, and Sequoia National Forest before reaching Isabella Lake. This river benefits from the waters of many tributaries, one of which is the Little Kern River. Both the Kern and its South Fork converge at Lake Isabella, and from there, the Lower Kern River continues its journey to Bakersfield.

The Kern is home to wild rainbow and brown trout. Additionally, there's a significant stocked population of hatchery rainbows. Native Kern River rainbows share genetics with coastal rainbow trout and golden trout. Most of the rainbows range from 10-12 inches, although three-pound fish are regularly caught. Robust insect populations provide ample food for these trout, including a variety of mayflies, stoneflies, and terrestrials.

Trout can become fairly active in April, with spring runoff not occurring until May in most years. Runoff typically subsides in June and trout will be prevalent throughout the river in the summer months. Larger brown trout can be found in the fall. As temperatures cool, the fish will move to slower, deeper water and become less active.

Much of the Kern is accessible by roads paralleling the river, including Highway 178, Route 521, and Mountain Highway 99. The river upstream of Johnsondale Bridge can only be accessed via hiking trails, however. Numerous campgrounds and lodges lie along the river, and hotels are available in Bakersfield. Due to the native trout populations, some regulations exist on certain stretches of the river, so be sure to check before you head out.