Relief Peak is located in the Emigrant Wilderness Area, which is just north of Yosemite National Park. The peak is the western most conclusion of a volcanic cirque that surrounds Soda Canyon. A volcanic ridge of red and black rock, and craggy spires, connects Relief Peak with Molo Mountain to the east, and then ultimately Kennedy Peak which completes the cirque to the north of Molo. The western face of Relief Peak drops off dramatically and overlooks Lunch Meadow. The Relief Peak Formation is geologically significant as it is one of several volcanic vents from which ancient volcanic mudflows originated. Mudflow breccia flowed as far as the Central Valley, forming what today appears to be an inverted river of volcanic rock when viewed from above. This page provides a very nice overview of the volcanic history with aerial photos of the lava flow.
The easiest routes to the summit are easy class II scrambles, however Relief Peak sees very few climbers each year. There are also several other peaks in the area that can be climbed during a weekend, including Kennedy Peak, Molo Mountain, Leavitt Peak, Blackhawk Mountain and Granite Dome.
What was formerly the Emigrant Basin was designated as the Emigrant Wilderness Area (EWA) on January 4, 1975. The 113,000 acre EWA is about 25 miles in length and up to 15 miles in width. It is bordered by Yosemite National Park on the south, the Hoover Wilderness Area on the east, and State Highway 108 and the Carson-Iceberg Wilderness Area on the north.
The EWA does not have the dramatic scenary of Yosemite Valley, however it also does not have the crowds that Yosemite has during the summer. The glaciated lanscape is consistent with that found in the backcountry of beautiful northern Yosemite. The northeastern third of the Wilderness is dominated by volcanic ridges and peaks; the remaining areas consist of many sparsely vegetated, granitic ridges interspersed with numerous lakes and meadows. There are over 100 lakes and 22 named peaks within the EWA. Elevations range from below 5000 feet near Cherry Reservoir to 11,570 feet at Leavitt Peak, but the elevation range of most of the popular high use areas is 7500 to 9000 feet. Precipitation averages 50 inches annually, 80 percent of it in the form of snow. Snowpacks typically linger into June, sometimes later following very wet winters. Summers are generally dry and mild, but afternoon thundershowers occur periodically and nighttime temperatures could dip below freezing anytime.
Relief Peak is most easily accessible from the Huckleberry Trail. Begin at the Kennedy Meadows trailhead off of Highway 108, just west of the Sonora Pass.
The trailhead is located at the end of the parking area for the Kennedy Meadows Resort. Overnight parking at the resort lot is $5/night and can be paid at the resort lobby. Alternatively, free parking is available at the signed forest service "trailhead" parking lot, which is located about 3/4 mile from the trailhead. Kennedy Meadows also operates a pack (horse) station. They will let you park overnight for free (and shower for free upon return) if you pack in with them one-way. They also have rental cabins, a supply store, small restaurant and saloon. The easiest routes to the summit are from Grouse Lake (6 miles), Soda Canyon (8 miles) or Lunch Meadow (9 miles).
Free wilderness permits are required for overnight stays in the Emigrant Wilderness Area. Call the Summit ranger station at (209) 965-3434 near Pinecrest ahead of time and they will prepare a permit for you in advance.
The climbing season varys each year depending on how much snow the area receives during the winter months. Hwy 108 closes during the winter, making winter access more difficult. So typically the most popular time to climb the mountain is from June through October.
There is excellent camping along Kennedy Creek, half mile west of Kennedy Lake. The camping in Soda Canyon is not very good. Kennedy Lake offers an added benefit of having great fishing for German Brown Trout up to 16".
There is good camping in the meadows a mile or so before you get to Grouse Lake. The camping at Grouse Lake is not very good, and there are no fish in the lake.
There is a hugh campsite at Sheep Camp, but it is used heavily by the Kennedy Meadows pack station. There are also some very good campsites in the Lodgepole stands 1/2 mile or so east of Sheep Camp, just before you reach Lunch Meadow.
Addition by Lakenyon: Another good place to camp is downstream (NW) from Sheep Camp, near the junction of Summit Creek and the creek that drains Lewis Lakes.
"This seeming complexity and profusion of names arises only because the named features cluster around the spot where four quadrangles have a common corner. The name 'Relief Valley' comes from an episode in 1852 when a party of emigrants were caught in an early snowstorm on the east side of the mountains. They abandoned their wagons, crossed the summit on foot to a sheltered spot on the west side, and sent some of their number for help. (Historic Spots, 566.) 'This valley takes its very appropriate name from the fact that it was here that relief was brought to the emigrants in their almost starving condition, from the generous-hearted citizens of Sonora and Columbia.' (Hutchings, Illustrated 2, May 1858: 494.)
'Relief Valley' is on Goddard's Map of Sonora Pass, 1853. Apparently this was what is now the site of 'Relief Reservoir.' It was called 'Lower Relief Valley' on the 1883 GLO plat and in the field notes of the surveyor. The creek was called 'Relief Valley Creek' in those same documents. The peak, creek, and 'Relief Valley' are on the Wheeler Survey atlas sheet 56D, 1878-79. The present array of names came into being on the four 15-minute quads in 1956." - Peter Browning, Place Names of the Sierra Nevada