Teton Range, Wyoming: Peaks, Geology and Visiting Grand Teton National Park

The Teton Range rises straight out of the floor of Jackson Hole in northwest Wyoming, with no foothills to soften the view. Grand Teton tops the skyline at 13,775 feet (4,199 m), and on a clear morning the whole wall of granite and snow seems close enough to touch from the valley road.

Teton Range facts: peaks and heights

The range runs about 40 miles (64 km) north to south, just east of the Idaho state line. Most of its eastern face lies inside Grand Teton National Park. The best-known summits form a tight cluster in the centre of the range:

• Grand Teton – 13,775 ft (4,199 m), the highest point
• Mount Owen – 12,928 ft (3,940 m)
• Middle Teton – 12,804 ft (3,903 m)
• Mount Moran – 12,605 ft (3,842 m), the broad massif above Jackson Lake
• South Teton – 12,514 ft (3,814 m)
• Teewinot Mountain – 12,325 ft (3,757 m)

The name probably comes from French-speaking trappers, who called the three main peaks les trois tétons. The Shoshone are said to have called the range Teewinot, “many pinnacles”, a name now carried by one of the peaks.

How the Teton fault built the mountains

The Tetons are one of the youngest ranges in North America. According to the National Park Service geology overview, movement on the Teton fault began roughly 10 million years ago. The block west of the fault tilted upward to form the mountains, while the block to the east dropped to become Jackson Hole. Total movement on the fault is probably more than 25,000 feet.

The rock itself is far older. Much of the range is gneiss about 2.7 billion years old, cut by granite that intruded around 2.5 billion years ago and by dark diabase dikes roughly 775 million years old. The same layer of Flathead sandstone that caps Mount Moran about 6,000 feet above the valley lies some 20,000 feet below the valley floor on the other side of the fault.

Ice did the finishing work. Pleistocene glaciers turned V-shaped river canyons into U-shaped ones and left moraines that now hold lakes such as Jenny Lake. The last major advance, the Pinedale glaciation, lasted from about 50,000 to 12,000 years ago. Around a dozen small glaciers survive today; Teton Glacier, below the northeast face of Grand Teton, is the largest.

Lakes, rivers and wildlife of Grand Teton National Park

A string of glacial lakes lines the base of the range: Jackson, Jenny, Leigh, Bradley, Taggart, Phelps and others. Jackson Lake is the giant, about 15 miles (24 km) long and 438 feet (134 m) deep. More than 100 small alpine lakes sit higher up, including Lake Solitude at 9,035 feet.

The Snake River flows south through the park from its headwaters in Yellowstone. Its wetlands at Oxbow Bend, near Moran, are one of the classic places to see the peaks reflected in water. Elk number in the thousands and are easiest to spot in spring and autumn; moose, bison, pronghorn, bighorn sheep, wolves, and black and grizzly bears also live here, along with more than 300 recorded bird species, from trumpeter swans to calliope hummingbirds.

Visiting the Tetons from Jackson Hole

Grand Teton National Park was created in 1929 and enlarged in 1950, when most of Jackson Hole National Monument was added. It now covers about 310,000 acres and drew more than 3.8 million visitors in 2025. The town of Jackson is the main base, and Jackson Hole Airport sits inside the park, the only commercial airport within an American national park. Yellowstone lies about 10 miles to the north, linked by the John D. Rockefeller Jr. Memorial Parkway.

Mid-July through August brings warm days, cool nights and frequent afternoon thunderstorms, so start hikes early. From December to April snow covers both the mountains and the valley, with sunny spells between storms and very cold nights. Check Grand Teton’s current conditions before you go, because roads and trailheads change with the season and with construction work.

For another North American mountain-and-lake landscape, explore Waterton Lakes. For a photographer’s broader regional story, continue with Mark Flower’s Colorado collection, or head west to Olympic National Park, where mountains meet temperate rainforest.

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