Analysing terrain data
The exposure grade describes the potential consequences of falling or slipping off the path.
Low Exposure: The path is on completely flat land and potential injury is limited to falling over.
Medium Exposure: The trail contains some obstacles such as outcroppings and rock which could cause injury.
High Exposure: Some trail sections have exposed ledges or steep ascents/descents where falling could cause serious injury.
Extreme Exposure: Some trail sections are extremely exposed where falling will almost certainly result in serious injury or death.
The John Muir Trail follows the crest of the Sierra Nevada through the most impressive stretch of this extensive range.
The trail is named for the legendary 19th-century naturalist John Muir, who helped explore this formerly trackless wilderness and raised a resounding voice for its conservation.
Beginning in Yosemite National Park and finishing on Mount Whitney, the 210-mile thru-hike is revered for epic scenery and sublime solitude among alpine peaks and basins that are hard to reach any other way. The sights of the JMT are unparalleled by perhaps any other trail of similar distance.
It begins with views of thundering Yosemite waterfalls and the gigantic face of Half Dome, with the option to climb the cables to its summit (additional permit required).
It then climbs into the Tuolumne Meadows high country before departing the national park for an extended journey through true backcountry of alpine lakes, glacial cirques, and mountain passes.
Culminating in a hard-earned climb to the summit of Mt.
Whitney, the highest point in the contiguous United States at 14,505 feet elevation, the JMT really is a trek like no other. As one of the most coveted thru hikes in the country, and one that partially shares a route with the Pacific Crest Trail, you will certainly encounter other hikers on the JMT.
The number is limited by a permit system, however, so you are guaranteed an uncrowded wilderness experience.
You must get a permit in advance or as a walk-in from the agency office where you begin the hike.
Note that if you plan to start from the south at Whitney Portal, you will also need the Mount Whitney Trail lottery permit. Most thru-hikers begin in the north at Yosemite.
This not only simplifies the permit system but provides other advantages as well.
With most of the JMT above 8,000 feet, altitude is a real concern.
From the north, the ascent is more gradual, so you’ll have time to acclimate.
Also, there are more supply stops along the northern half of the trail, so you can carry fewer supplies during the early miles and allow your body to adjust. Camping is at large almost everywhere along the JMT, with no amenities available, so you must be completely self-sufficient and Leave No Trace.
Hikers usually have packages mailed to supply stops for holding.
In the southern half, where there are no supply stops along the trail, you can depart at strategic places, which may require hiking an extra day and night on a side trip to resupply and return. Sources: https://en.wikipedia.org/wiki/John_Muir_Trail https://www.pcta.org/discover-the-trail/john-muir-trail/