The most popular route to the summit is by way of the Mount Whitney Trail which starts at Whitney Portal, at an elevation of 8,360 ft (2,550 m), 13 mi (21 km) west of the town of Lone Pine. The hike is about 22 mi (35 km) round trip with an elevation gain of over 6,100 ft (1,900 m). Permits are required year round, and to prevent overuse a limited number of permits are issued by the Forest Service between May 1 and November 1.[16] Most hikers do the trip in two days. Those in good physical condition sometimes attempt to reach the summit and return to Whitney Portal in one day, thus requiring only a somewhat easier-to-obtain "day use" permit rather than the overnight permit. This is considered an "extreme" day hike, which normally involves leaving Whitney Portal before sunrise and 12 to 18 hours of strenuous hiking,[17] while struggling with altitude sickness, cold air, and occasionally treacherous surface conditions (because snow and/or ice are normally present on parts of the trail, except for a short period from early July to late September.)

Longer approaches to Whitney arrive at its west side, connecting to the Mount Whitney Trail near the summit by way of the John Muir Trail.
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