Mammoth Peak is at the northern end of the Kuna Crest in Yosemite National Park, very close to CA State route 120. Its summit appears rounded and rocky from the road. Not nearly as popular as the higher peaks in the area, it still provides great summit views and of course, easy access.
Most approaches to Mammoth Peak can be found off CA State route 120 just west of the Tioga Pass entrance station. You can simply find a parking spot along the road with a good view of the peak, walk to the base and start the climb up. Or, you can spend a little more time in this beautiful area by starting at the Mono Pass trailhead, sometimes referred to as the Dana Meadows trailhead. It’s about 1.4 miles west of the Tioga Pass entrance station on CA State route 120. A small paved parking lot, with room for a couple dozen vehicles, is found at the trailhead. There is also a toilet and a number of bear-proof food lockers. Arrive early if you want a parking space; otherwise, parking seems to be tolerated along the narrow roadside. No camping is allowed at this trailhead, but vehicles are allowed to remain overnight.
Follow the Mono Pass trail into the forest of dense lodgepole pines. Along the way, you’ll have views of Mammoth Peak on your right whenever the forest opens up. You can pretty much pick your own point to leave the trail and head cross country toward the mountain. Leaving the trail at its junction with the Spillway Lake trail works well. You’ll need to cross the Parker Pass Creek and make your way up through some forested area before you get another clear view of your objective. Once it’s in sight, you can easily pick your own class 1-2 route to the summit. On the return, a stop at Kuna Lake is worth your time. Following the creek that flows from this lake back down toward the trail will provide lots of great scenery. Once the creek flows into Parker Pass Creek, cross the creek to return to the Mono Pass trail.
If you do this as a day hike no permits are required, you just need to pay the entrance fee to the park. You can find all the pertinent red tape information for Yosemite National Park at the Tuolumne Meadows - Logistical Center page.
The Tuolumne Meadows – Logistical Center page contains detailed car camping, backcountry camping and traditional lodging information for Yosemite NP. Similar choices for camping in the Lee Vining Area, just east of Yosemite, are listed on this Inyo National Forest page.