The ascent begins at High Emigrant Lake, which is located 16 miles from the trailhead at Kennedy Meadows Resort.
The Kennedy Meadows trailhead is located off of CA Highway 108, just west of the Sonora Pass. Directions are available on the Kennedy Meadows Resort
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.
Follow the Huckleberry trail for 12 miles. Just after Lunch Meadow, take the trail split east to Brown Bear Pass. Continue on this trail until you reach Emigrant Meadow Lake. Turn NE and head cross country, following the stream that feeds into Emigrant Meadow Lake, until you reach Red Bug Lake. The trail to Big Sam runs just east of Red Bug Lake, near High Emigrant Lake. (16 miles total)
Follow the jeep road north along the western shore of High Emigrant Lake. The first mile is nearly level hiking with a gradual ascent as you near the base of the mountain. You'll see the obvious switchbacks
of the road winding up the south side of Big Sam. Follow the dirt road all the way to the summit. There are quite a few switchbacks and it is very barren with no water once you start the climb. Fill your water bottle one last time from the stream that feeds High Emigrant Lake, just east of the road. Once the road tops out, the summit is just a few steps to the east.
No special equipment is needed later in the summer other than for overnight backcountry camping. However, you might consider bringing crampons and/or ice axe earlier in the season if you plan to descend the north side of the mountain, unless you are extremely knowledgeable and comfortable crossing exposed ice/snowfields without them.
(Also see my trip report
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