Mt. Lyell is the highest peak in Yosemite National Park. Located near the southeast boundary, it is a very popular destination despite its long distance (13.5 mi) from the nearest trailhead. It is easily recognizable from the summit of most peaks in Yosemite, thanks to the prominent Lyell Glacier on its northern flank, the largest in the park. An ancient metamorphosed slate tops the summit, which overlays a younger granite base.
Mt Lyell stands at the triple divide between two great Sierra rivers (the Merced and Tuolumne Rivers) and Rush Creek (which feeds Mono Lake).
For highpoint seekers, Mt. Lyell is the highest point in Tuolumne county, one of the more difficult of the 58 California county highpoints. It is most easily approached via Lyell Canyon from Tuolumne Meadows.
The closest and most popular trailhead is at Tuolumne Meadows, off US120. Just east of the Tuolumne Meadows campground, there is a turnoff for the Tuolumne Lodge and Wilderness Permits. Pass the large lot for Wilderness permits (unless you need to get one!), and drive past the Ranger Station on the left side of the road. Before you reach the Tuolumne Lodge, there is a large parking lot on the left side. There are bear boxes there that you can leave food items that you do not take with you. Use them! Bears are rampant in these parts and will happily destroy your car to get a meal.
The trailhead is on the south side of the road, opposite the parking lot.
Alternatively, you can approach Mt. Lyell from the east via Rush Creek at Silver Lake Resort (near June Mtn Ski area) or Agnews Meadow near Mammoth Lakes (this is the longer of the two). Take the JMT to Donohue Pass to reach the Lyell Fork drainage. From a map it may be enticing to try approaching from the east via Marie Lakes instead of Donohue Pass, but be warned this is a class 4 route, and will certainly take longer. These routes are longer than approaching from Tuolumne Meadows and require more elevation gain.
$20 fee to enter Yosemite NP. Good for seven days.
Wilderness permits are required for overnight camping. These can be obtained at any Ranger Station in Yosemite, including the station at Tuolumne Meadows (on the right as you turn off to park for the trailhead). Permits for the Lyell Fork of the Tuolumne Meadows are very popular and likely to be unavailable on weekends unless you arrive early to stand in line. Consider stopping at the entrance station on US120 if arriving from the west and getting a permit the night before.
Campfires are not permitted above 10,000 feet. Also, YNP regulations state the following: You must camp at least four trail miles from Tuolumne Meadows, Yosemite Valley, Glacier Point, Hetch Hetchy, and Wawona, and at least one air mile from any road. Camping is prohibited in the Dana Fork of the Tuolumne River.
When To Climb
Climbing is usually done May-Oct when the Tioga Road (US120) through Tuolumne Meadows is open. After Oct 15 the road is sometimes open, but overnight parking is no longer permitted.
Overnight camping is allowed in the Yosemite Wilderness with a valid permit (see above). For a climb of Mt. Lyell most parties camp in the upper portion of Lyell Canyon (where there are still trees), or in the sparser flat areas in the smaller canyons to the west of the JMT along the route.
"Named on July 2, 1863, by William H. Brewer and Charles F. Hoffmann of the California Geological Survey.
'Mount Lyell, for Sir Charles Lyell (1797-1875), whose admirable geological works have been well known to students of this branch of science, in this country, for the past thirty years.' (Whitney, Yosemite Guide-Book, 1870, 100.)
Mount Lyell is the highest peak in Yosemite National Park. The first ascent was by John Boies Tileston of Boston, on August 29, 1871. 'I was up early the next morning, toasted some bacon, boiled my tea, and was off at six. I climbed the mountain, and reached the top of the highest pinnacle ("inaccessible," acording to the State Geological Survey), before eight. I came down the mountain, and reached camp before one, pretty tired.' (SCB 12, no. 3, 1926: 305.)"
- Peter Browning, Place Names of the Sierra Nevada
"July 2 we are up early. First, a hasty and substantial breakfast, then we prepare to climb the highest peak back. The frost lies heavy on the grass, and we are some distance before the sun peeps over the hill. Over rocks and snow, the last trees are passed, we get on bravely, and think to be up by eleven o'clock. We cross great slopes all polished like glass by former glaciers. Striking the last great slope of snow, we have only one thousand feet more to climb. In places the snow is soft and we sink two or three feet in it. We toil on for hours; it seems at times as if our breath refuses to strengthen us, we puff and blow so in the thin air.
After over seven hours of hard climbing we struck the last pinnacle of rock that rises through the snow and forms the summit -- only to find it inaccessible, at least from that side. We had to stop at 125 or 150 feet below the top, being something over 13,000 feet above the sea, the baromter standing 18.7 inches. As we had named the other mountain Mount Dana, after the most eminent of American geologists, we named this Mount Lyell, after the most eminent of English geologists.
- William Brewer, Up and Down California
The route chosen by Brewer and Hoffmann appears to be the standard route up the Lyell glacier on the peaks north side, a straightforward class 2-3 climb, so it remains unclear why they found the route "inaccessible".