Yosemite National Park covers about 3,070 km² (1,187 sq mi) of the central Sierra Nevada in California. It is known for granite walls and domes that glaciers and rockfall shaped out of a single great body of cooled magma: El Capitan, about 914 m (3,000 ft) from base to summit; Half Dome, rising some 1,460 m (4,800 ft) above the valley floor; and Yosemite Falls, which drops a combined 739 m (2,425 ft). Abraham Lincoln protected the valley and the Mariposa Grove of giant sequoias in the Yosemite Grant of 1864, Congress created the national park on 1 October 1890, and it joined UNESCO's World Heritage List in 1984. It now draws about four million visitors a year, with a record of more than five million in 2016. The highest point is Mount Lyell at about 4,000 m (13,120 ft).
Granite Born Six Miles Underground: The Sierra Nevada Batholith
Almost every cliff in Yosemite is cut from the Sierra Nevada Batholith, a vast mass of intrusive igneous rock that cooled deep below the surface. The first phase of this plutonism began about 210 million years ago in the late Triassic and continued through the Jurassic to about 150 million years ago; a second phase ran from roughly 120 to 80 million years ago in the Cretaceous. The resulting granite and granodiorite lay about 9.7 km (6 miles) underground. Only around five per cent of the park's landforms, mostly on its eastern edge near Mount Dana, are older metamorphosed volcanic and sedimentary rock, remnants of the "roof" that once sat over the magma.
Bringing that granite to the surface took tilting and uplift. Starting about 10 million years ago, movement on the Sierra fault lifted the range and tipped it towards the west, steepening the Merced and Tuolumne rivers so they cut deep, narrow canyons. Uplift accelerated again about two million years ago. As the overlying rock was stripped away, the released granite expanded and peeled off in curved sheets, a process called exfoliation. Where joints in the rock were widely spaced, exfoliation produced domes such as Half Dome and North Dome and the inset Royal Arches; where cross joints were close together, it left pillars like Washington Column and Lost Arrow. For more on the wider range these rocks belong to, see our guide to the Sierra Nevada.
How Ice and Rockfall Carved Yosemite Valley
A series of glaciations, starting two to three million years ago and ending around 10,000 years ago, reshaped those river canyons. At least four major glacial stages are recognised in the Sierra, known locally as the Sherwin, Tahoe, Tenaya and Tioga. The Sherwin glaciers were the largest, filling Yosemite Valley and its neighbours with ice up to 1,200 m (4,000 ft) thick, and a Sherwin-age glacier almost certainly did most of the excavation that turned the V-shaped Merced canyon into a U-shaped trough. The longest glacier ran 97 km (60 miles) down the Grand Canyon of the Tuolumne, beyond Hetch Hetchy Valley. Only the highest summits, Mount Dana and Mount Conness among them, stayed above the ice.
John Muir was one of the first to argue that alpine glaciers made the valley, against the state geologist Josiah Whitney. Later work gave a more nuanced answer: geologists now estimate that only about 10 per cent of the valley's widening and 12 per cent of its deepening were due to glaciation, with the rest coming from rockfall controlled by the joints in the granite. That process has not stopped. On 6 July 1996 an estimated 60,000 to 80,000 tons of rock fell about 550 m (1,800 ft) from the east side of Glacier Point, killing one person. When the last glacier retreated, recessional moraines dammed Lake Yosemite, a shallow lake about 9 km (5.5 miles) long that periodically covered much of what is now the flat valley floor, about 1,200 m (4,000 ft) above sea level.
Tunnel View and El Capitan's 914-Metre Wall
Most visitors enter the valley from the west and get their first view at Tunnel View. The panorama takes in El Capitan on the left, Bridalveil Fall and Cathedral Rocks on the right, and Half Dome at the far end. Yosemite Valley itself is about 12.1 km (7.5 miles) long and 910–1,070 m (3,000–3,500 ft) deep, yet it makes up only about one per cent of the park.
El Capitan stands on the valley's north side near its western end. The Mariposa Battalion named it in 1851, taking El Capitán ("the captain") as a loose translation of the Miwok name Tutokanula, which Lafayette Bunnell rendered as "rock chief"; the Miwok basket-weaver Julia Parker gave another meaning, "inchworm rock", from a creation story. Its most famous big-wall route is The Nose, up the central prow. Warren Harding, Wayne Merry and George Whitmore first climbed The Nose in 1958 over 47 days; Lynn Hill free-climbed it in 1993; and on 3 June 2017 Alex Honnold climbed the Freerider route without ropes in 3 hours and 56 minutes.
Half Dome, Glacier Point and the Giant Staircase
At the valley's eastern end, Half Dome rises to a summit more than 2,680 m (8,800 ft) above sea level. Its sheer northwest face makes it look like a dome sliced in two, but from Washburn Point it shows up as a thin ridge, and geologists think up to 80 per cent of the "missing" half was never there. Josiah Whitney called it "perfectly inaccessible" in the 1870s; George Anderson reached the top in October 1875 by drilling iron eyebolts into the rock. Today hikers follow a trail of about 13 km (8.2 miles) from the valley floor with 1,460 m (4,800 ft) of climbing, finishing with 120 m (400 ft) between steel cables first put up in 1919. Because traffic reached as many as 1,000 people a day, a permit system began in 2010, with 300 permits a day when the cables are up.
Across the valley, Glacier Point sits 992 m (3,254 ft) above the floor. Beneath it, the Merced River descends the "Giant Staircase" from Little Yosemite Valley: first Nevada Fall, 181 m (594 ft), then Vernal Fall, 97 m (317 ft), before it flows past Happy Isles into the valley. Clouds Rest, at 3,025 m (9,924 ft), is the highest point near the valley.
Yosemite Falls and the Valley's Hanging Valleys
The waterfalls exist because the main valley was cut down far faster than its side valleys, first by the steepened Merced and then by ice, leaving tributary streams to spill off "hanging valleys" high on the walls. Yosemite Creek, after meandering through Eagle Creek Meadow, drops over the north rim as Yosemite Falls in three sections: the Upper Fall, a 440 m (1,430 ft) plunge; the Middle Cascades, four smaller drops totalling 206 m (675 ft) that most viewpoints miss; and the Lower Fall, 98 m (320 ft). The World Waterfall Database ranks the total as the fourth-tallest waterfall in North America. Flow peaks in April, May and June with the snowmelt, and in all but the wettest years the falls stop altogether by late summer. Our separate guide to Yosemite Falls covers the trails to the top.
Ribbon Fall carries much less water but has the park's highest single vertical drop, 491 m (1,612 ft). Horsetail Fall, a small winter stream over the eastern edge of El Capitan, can glow orange at sunset on clear evenings in mid to late February.
Mariposa Grove and the Tuolumne High Country
About 95 per cent of the park is designated wilderness, and most of it lies far above the valley. In the south, near Wawona, the Mariposa Grove is the largest of the park's three giant sequoia groves; the others are the Tuolumne and Merced groves. Galen Clark and Milton Mann were the first non-Native visitors in 1857, and Clark counted 427 mature trees. Two of the grove's trees rank among the 30 largest giant sequoias in the world. In 1881 a stagecoach company cut a tunnel through the Wawona Tree; a second, the California Tunnel Tree, was cut in 1895 and is still alive. The grove closed for a restoration project from 2015 and reopened on 15 June 2018 without private car access, and it now gets about one million visitors a year.
To the east, Tuolumne Meadows lies at about 2,627 m (8,619 ft) along the Tuolumne River, a subalpine meadow at an elevation where the park's precipitation peaks at around 1,300 mm (50 in) a year, mostly as winter snow. The Tioga Pass Road (State Route 120) crosses the meadows but closes when the high country is snowed in. Higher still, the Lyell Glacier covers about 65 ha (160 acres) and is the largest in the park, but neither it nor the Maclure Glacier is a relic of the Ice Age; both formed in later cold spells and have shrunk over the past century. The Merced and Tuolumne both begin inside the park and are federally designated Wild and Scenic Rivers. On the Tuolumne, the O'Shaughnessy Dam, approved under the Raker Act of 1913 over the opposition of Muir and the Sierra Club, flooded Hetch Hetchy Valley to supply San Francisco.
From the Ahwahneechee to the 1864 Yosemite Grant and the 1890 Park
The valley's first people called themselves the Ahwahneechee, after their name for the valley, Ahwahnee ("big mouth"). The word Yosemite comes from the Miwok yohhe'meti, "they are killers", a name neighbouring Miwok used for the Ahwahneechee; Bunnell wrongly believed it meant "grizzly bear". In March 1851 the state-funded Mariposa Battalion under James Savage entered the valley during the Mariposa War, which historians count as part of the California genocide, and in May, under John Boling, it captured 35 Ahwahneechee, including Chief Tenaya. Native families stayed on in reduced numbers, and the Park Service evicted the last residents of the Indian village in 1969.
Tourism began in 1855 with James Mason Hutchings and the artist Thomas Ayres. On 30 June 1864 Lincoln signed the Yosemite Grant, ceding the valley and Mariposa Grove to California: the first time the US government set land aside for preservation and public use, eight years before Yellowstone became the first national park. Muir and the editor Robert Underwood Johnson then lobbied for the Act that created Yosemite National Park on 1 October 1890 around the state-run core. After Theodore Roosevelt camped with Muir near Glacier Point in May 1903, Roosevelt signed the 1906 bill that returned the valley and grove to federal control. The National Park Service took over in 1916, Congress designated about 89 per cent of the park as the Yosemite Wilderness in 1984, and in 2024 the park received over four million visitors, most of whom spend their time on the valley's 18 km² floor.