page_title: Three Sisters (Oregon)
section_title: Human history
hierarchical_section_title: Three Sisters (Oregon) / Human history
caption_attribution_description: English: Peter Skene Ogden, late in life. Taken sometime before his death in 1854
context_page_description: The Three Sisters are closely spaced volcanic peaks in the U.S. state of Oregon. They are part of the Cascade Volcanic Arc, a segment of the Cascade Range in western North America extending from southern British Columbia through Washington and Oregon to Northern California. Each more than 10,000 feet in elevation, they are the third-, fourth- and fifth-highest peaks in Oregon. Located in the Three Sisters Wilderness at the boundary of Lane and Deschutes counties and the Willamette and Deschutes national forests, they are about 10 miles south of the nearest town, Sisters. Diverse species of flora and fauna inhabit the area, which is subject to frequent snowfall, occasional rain, and extreme temperature variation between seasons. The mountains, particularly South Sister, are popular destinations for climbing and scrambling.
  Although they are often grouped together as one unit, the three mountains have their own individual geology and eruptive history. Neither North Sister nor Middle Sister has erupted in the last 14,000 years, and it is considered unlikely that either will ever erupt again.
context_section_description: The Three Sisters area was occupied by Amerindians since the end of the last glaciation, mainly the Northern Paiute to the east and Molala to the west. They harvested berries, made baskets, hunted, and made obsidian arrowheads and spears. Traces of rock art can be seen at Devils Hill, south of South Sister.
  The first Westerner to discover the Three Sisters was the explorer Peter Skene Ogden of the Hudson Bay Company in 1825. He describes "a number of high mountains" south of Mount Hood. Ten months later in 1826, the botanist David Douglas reported snow-covered peaks visible from the Willamette Valley. As the Willamette Valley was gradually colonized in the 1840s, Euro-Americans approached the summits from the west and probably named them individually at that time. Explorers, such as Nathaniel Jarvis Wyeth in 1839 and John Frémont in 1843, used the Three Sisters as a landmark from the east. The area was further explored by John Strong Newberry in 1855 as part of the Pacific Railroad Surveys.
  In 1862, to connect the Willamette Valley to the ranches of Central Oregon and the gold mines of eastern Oregon and Idaho, Felix and Marion Scott traced a route over Scott Pass. This route was known as the Scott Trail, but was superseded in the early 20th century by the McKenzie Pass Road further north. Around 1866, there were reports that one of the Three Sisters emitted some fire and smoke.
  In the late 19th century, there was extensive wool production in eastern Oregon. Shepherds led their herds of 1,500 to 2,500 sheep to the Three Sisters. They arrived in eastern foothills near Whychus Creek by May or June, and then climbed to higher pastures in August and September. By the 1890s, the area was getting overgrazed. Despite regulatory measures, sheep grazing peaked in 1910 before being banned in the 1930s at North and Middle Sister, and in 1940 at South Sister.
  In 1892, President Grover Cleveland decided to create the Cascades Forest Reserve, based on the authority of the Forest Reserve Act of 1891. Cascades Reserve was a strip of land from 20 to 60 miles (30 to 100 km) wide around the main crest of the Cascade Range, stretching from the Columbia River almost to the border with California. In 1905, administration of the Reserve was moved from the General Land Office to the United States Forest Service. The Reserve was renamed the Cascade National Forest in 1907. In 1908, the forest was split: the eastern half became the Deschutes National Forest, while the western half merged in 1934 to form the Willamette National Forest.
  Most of the Three Sisters glaciers were described for the first time by Ira A. Williams in 1916. Collier Glacier, between North and Middle Sister, was first studied and mapped by Edwin Hodge. Ruth Hopsen Keen took a forty-year photographic record of Collier Glacier, documenting part of the 0.93-mile (1,500 m) retreat of the glacier from 1910 to 1994.
  In the 1930s, the Three Sisters were part of a proposed National Monument. To maintain its authority over the region, the Forest Service decided to create a 191,108-acre (773 km²) primitive area in 1937. The following year, at the instigation of Forest Service employee Bob Marshall, it was expanded by 55,620 acres (225 km²) in the French Pete Creek basin. In 1957, the Forest Service decided to reclassify the area as a wilderness area and removed the old-growth forest of the French Pete Creek basin, despite protests of local environmental activists. The area became part of the National Wilderness Preservation System when the Wilderness Act of 1964 was passed, but the area still excluded the French Pete Creek basin. Responding to environmental mobilization throughout the state of Oregon, Congress passed the Endangered American Wilderness Act of 1978, which led to the reinstatement of French Pete Creek and its surroundings in the Three Sisters Wilderness Area. The Oregon Wilderness Act of 1984 further expanded the wilderness with the addition of 38,100 acres (154 km²) around Erma Bell Lakes.
caption: Portrait of Peter Skene Ogden, discoverer of the Three Sisters, circa 1854
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