Begin in the Reds Meadow Valley at the Rainbow Falls shuttle stop. It’s a one-mile hike to Rainbow Falls where the 100-foot falls are a scenic picnic spot. This trail goes 13 miles (one way) out to a natural hot spring, Iva Bell, which is popular with overnight backpackers (permit required). Horseback trips are offered in this area. Connects with John Muir and Pacific Crest Trails. All visitors ride a shuttle bus from Mammoth’s Main Lodge parking lot down into the valley floor (small fee applies).