Just in case you have no idea about the JMT. The JMT is the John Muir Trail is in California and starts in the valley of Yosemite National Park and ends at the top of Mt. Whitney some 211 miles later. Then one has to hike another 7 miles down to the valley.
The trail goes through several national parks, national forests, and wilderness areas. The trail goes over 11 passes with the highest pass being Forester pass at 13,200′. Here is link if you want more information about the trail. In general, on average people take between two or three weeks to complete.
Journeys with Jeff and Ellen 