Twin Falls is the largest city of Idaho's Magic Valley region. As the largest city in a 100-mile (160-kilometer) radius, Twin Falls serves as a regional commercial center for both south-central Idaho and northeastern Nevada.
Twin Falls is the principal city of the Twin Falls, ID Micropolitan Statistical Area, which officially includes Jerome and Twin Falls Counties. The resort community of Jackpot, Nevada, in Elko County is unofficially considered part of the greater Twin Falls area.
Excavations at Wilson Butte Cave near Twin Falls in 1959 revealed evidence of human activity, including arrowheads, that rank among the oldest dated artifacts in North America. Later native American tribes predominant in the area included the Northern Shoshone and Bannock.
The first people of European ancestry to visit the Twin Falls area are believed to be members of a group led by Wilson Price Hunt, which attempted to blaze an all-water trail westward from St. Louis, Missouri, to Astoria, Oregon, in 1811 and 1812. Hunt's expedition met with disaster when much of his expedition was destroyed and one man was killed in rapids on the Snake River known as Caldron Linn near present-day Murtaugh. Hunt and the surviving members of his expedition completed the journey to Astoria by land.
In 1812 and 1813, Robert Stuart successfully led an overland expedition eastward from Astoria to St. Louis which passed through the Twin Falls area. Stuart's route formed the basis of what became the Oregon Trail. Some 150 years later, Robert Stuart Middle School in Twin Falls was named in his honor.
To address this issue, in 1900 I. B. Perrine founded the Twin Falls Land and Water Company largely to build an irrigation canal system for the area. After an August 1900 survey of 244,025 acres (98,753.4 hectares) in the area, in October 1900 the company was granted the necessary water rights to begin construction of the irrigation system. Several lots in the surveyed area were set aside specifically for future townsites. These lots eventually became the settlements of Twin Falls, Kimberly, Buhl, Filer, Hansen and Murtaugh. In 1902 the project nearly failed as most of the original investors pulled out, with only Salt Lake businessman Stanley Milner maintaining a stake in the company.
By 1903 Perrine, who had been a successful farmer and rancher in the Snake River Canyon, had obtained private financing from Milner and others under the provisions of the Carey Act of 1894 to build a dam on the Snake River near Caldron Linn. Completed in 1905, Milner Dam and its accompanying canals made commercial irrigation outside the Snake River Canyon practical for the first time. As a result Perrine is generally credited as the founder of Twin Falls.
A land drawing was held for the future townsite in July 1903 with disappointing results. A much more successful drawing was held in October 1904. Twin Falls city was founded in 1904 as a planned community, designed by celebrated Franco-American architect Emmanuel Louis Masqueray, with proceeds from sales of townsite lots going toward construction of irrigation canals. Twin Falls was incorporated as a village on April 12, 1905. The city is named for a nearby waterfall on the Snake River of the same name. In 1907 Twin Falls became the seat of the newly formed Twin Falls County.
The original townsite follows a unique design. It is laid out on northeast-to-southwest and northwest-to-southeast roads. The northwest-to-southeast roads were numbered and called avenues, while the northeast-to-southwest roads were numbered and called streets. Only two central streets, the northwest-to-southeast Main Avenue and the northeast-to-southwest Shoshone Street, were named. It is purported that the reason this was done was to allow sun to come into every room in the home at some point during the day. This system created situations where one side of a street may have an entirely different address than the other, and where the corner of "3rd and 3rd," for example, was in more than one location. In 2003 the numbered northeast-to-southwest streets were renamed to alleviate decades of confusion. Later city roads, such as Blue Lakes Boulevard, Addison Avenue and Washington Street, are laid out in standard north–south and east–west orientations.
After Milner Dam was constructed agricultural production in south-central Idaho increased substantially. In 1909 the privately owned Twin Falls Land and Water Company was reorganized as the shareholder-owned Twin Falls Canal Company. Twin Falls became a major regional economic center serving the agriculture industry, a role which it has sustained to the present day. The city became a processing center for several agricultural commodities, notably beans and sugar beets. In later years other food processing operations augmented the local economy. By 1960, Twin Falls had become one of Idaho's largest cities even though its origins were still within living memory for many.
Twin Falls became the center of national attention in September 1974 when daredevil Evel Knievel attempted to jump the Snake River Canyon in a specially modified rocket cycle. Watched by millions on closed-circuit television on a Sunday afternoon, the attempt ultimately failed due to high winds and a premature deployment of Knievel's parachute. The launch ramp's foundation lies on private land on the canyon's south rim. Less than two miles west (3 km) of Shoshone Falls, it is still visible.
During the last quarter of the 20th century, gradual diversification of the agriculture-based economy allowed the city to continue to grow. Major Twin Falls employers in 2006 included computer maker Dell, Inc., Glanbia, and Jayco, a recreational vehicle manufacturer. In September 2009 Dell announced it would close its Twin Falls facility by January 2010. Later in 2010 the call center company C3 opened a facility in the former Dell location. In 2012 Chobani, one of the U.S.'s largest Greek style yogurt manufacturers, opened its largest factory and distribution center in Twin Falls.
In recent years Twin Falls has become quite multicultural. Thanks in large part to a refugee center operated by the College of Southern Idaho, since 1995 significant numbers of people from Bosnia and Herzegovina and the former Soviet Union have settled in Twin Falls. The city also has a sizable Hispanic population.