Mount Whitney Trail is the standard route to the summit of California’s Mount Whitney, the tallest peak in the contiguous United States. Beginning at Whitney Portal west of Lone Pine, it covers 21.4 miles round trip and gains more than 6,100 feet, following much of a pack route designed by engineer Gustave Marsh and opened in 1904. Its gentler alignment creates a long ascent along Lone Pine Creek, up 97 switchbacks to Trail Crest, then across the ridge to the summit shelter. Heavy summer and fall use is tightly regulated with permits and quotas, while weather, trail damage, bears, and human waste management shape travel on this demanding alpine route.