Snake River in the context of "Centennial Mountains"

Oregon (/ˈɒrɪɡən, -ɡɒn/ ORR-ih-ghən, -⁠gon) is a state in the Pacific Northwest region of the United States. It is a part of the Western U.S., with the Columbia River delineating much of Oregon's northern boundary with Washington, while the Snake River delineates much of its eastern boundary with Idaho. The 42° north parallel delineates the southern boundary with California and Nevada. The western boundary is formed by the Pacific Ocean.

Oregon has been home to many indigenous nations for thousands of years. The first European traders, explorers, and settlers began exploring what is now Oregon's Pacific coast in the early to mid-16th century. As early as 1564, the Spanish began sending vessels northeast from the Philippines, riding the Kuroshio Current in a sweeping circular route across the northern part of the Pacific. In 1592, Juan de Fuca undertook detailed mapping and studies of ocean currents in the Pacific Northwest, including the Oregon coast as well as the strait now bearing his name. The Lewis and Clark Expedition traversed Oregon in the early 19th century, and the first permanent European settlements in Oregon were established soon afterward by trappers and fur traders. The United States received joint occupation rights to the region from the United Kingdom through the Treaty of 1818. The Oregon Treaty of 1846 formally brought Oregon under American sovereignty, and the Oregon Territory was created two years later. Oregon was admitted to the United States on February 14, 1859, becoming the 33rd state.

Numic is the northernmost branch of the Uto-Aztecan language family. It includes seven languages spoken by Native American peoples traditionally living in the Great Basin, Colorado River basin, Snake River basin, and southern Great Plains. The word "Numic" comes from the cognate word in all Numic languages for "person", which reconstructs to Proto-Numic as /*nɨmɨ/. For example, in the three Central Numic languages and the two Western Numic languages, the word for "person" is /nɨmɨ/. In Kawaiisu it is /nɨwɨ/, and in Colorado River, it is /nɨwɨ/, /nɨŋwɨ/, and /nuu/.

The Columbia River (Upper Chinook: Wimahl or Wimal; Sahaptin: Nch’i-Wàna or Nchi wana; Sinixt dialect swah'netk'qhu) is the largest river in the Pacific Northwest region of North America. The river forms in the Rocky Mountains of British Columbia, Canada. It flows northwest and then south into the U.S. state of Washington, then turns west to form most of the border between Washington and the state of Oregon before emptying into the Pacific Ocean. The river is 1,243 mi (2,000 km) long, and its largest tributary is the Snake River. Its drainage basin is roughly the size of France and extends into seven states of the United States and one Canadian province. The fourth-largest river in the United States by flow, the Columbia has the greatest flow of any river into the eastern Pacific.

The Columbia and its tributaries have been central to the region's culture and economy for thousands of years. They have been used for transportation since ancient times, linking the region's many cultural groups. The river system hosts many species of anadromous fish, which migrate between freshwater habitats and the saline waters of the Pacific Ocean. These fish—especially the salmon species—provided the core subsistence for native peoples.

Henrys Fork is a tributary river of the Snake River, approximately 127 miles (204 km) long, in southeastern Idaho in the United States. It is also referred to as the North Fork of the Snake River. Its drainage basin is 3,212 square miles (8,320 km), including its main tributary, the Teton River. Its mean annual discharge, as measured at river mile 9.2 (Henrys Fork near Rexburg) by the United States Geological Survey (USGS), is 2,096 cubic feet per second (59.4 m/s), with a maximum daily recorded flow of 79,000 cubic feet per second (2,240 m/s), and a minimum of 183 cubic feet per second (5.18 m/s). It is normally transcribed without an apostrophe.

The river is named for Andrew Henry, who first entered the Snake River plateau in 1810. Employed by the Missouri Fur Company, he built Fort Henry on the upper Snake River, near modern St. Anthony, but abandoned this first American fur post west of the continental divide the following spring.

Mount Jefferson is a mountain located on the Continental Divide between Fremont County of northeastern Idaho and Beaverhead County of southwestern Montana. Mount Jefferson is the highest point of the Centennial Mountains, whose crest runs along the Continental Divide and can be climbed using a class 2 route (scramble) from the access road to neighboring Sawtell Peak.

The south and west slopes of Mount Jefferson drain into Hell Roaring Creek, thence into Red Rock Creek, the Red Rock River, the Beaverhead River, the Jefferson River, the Missouri River, the Mississippi River, and into the Gulf of Mexico.Brower's Spring, the source of Hell Roaring Creek, on the mountain's east flank in Montana, is considered the absolute headwaters of the Missouri River.The northeast slope of Mount Jefferson drains into the South Fork of Duck Creek, thence into Henrys Lake, the Henrys Fork of the Snake River, the Columbia River, and into the Pacific Ocean.

The Tri-Cities are three closely linked cities (Kennewick, Pasco, and Richland) at the confluence of the Yakima, Snake, and Columbia Rivers in the U.S. state of Washington. Located in the Columbia Basin of Eastern Washington, the cities border one another, making the Tri-Cities seem like one uninterrupted mid-sized city. The three cities function as the center of the Tri-Cities metropolitan area, which consists of Benton and Franklin counties. The Tri-Cities urban area includes the city of West Richland, the census-designated places (CDP) of West Pasco and Finley, as well as the CDP of Burbank, despite the latter being located in Walla Walla County.

The official 2023 estimate of the Tri-Cities MSA population is 314,253, a more than 24% increase from 2010, while the combined population of the three principal cities themselves was 228,482 according to 2023 estimates from the United States Census Bureau.

43°00′N 113°30′W / 43.000°N 113.500°W / 43.000; -113.500

The Snake River Plain is a geologic feature located primarily within the U.S. state of Idaho. It stretches about 400 miles (640 km) westward from northwest of the state of Wyoming to the Idaho-Oregon border. The plain is a wide, flat bow-shaped depression and covers about a quarter of Idaho. Three major volcanic buttes dot the plain east of Arco, the largest being Big Southern Butte.

Lewiston is a city in and the county seat of Nez Perce County, Idaho, United States, in the state's north central region. It is the third-largest city in the northern Idaho region, behind Post Falls and Coeur d'Alene, and the twelfth-largest in the state. Lewiston is the principal city of the Lewiston, ID-WA Metropolitan Statistical Area, which includes all of Nez Perce County and Asotin County, Washington. As of the 2020 census, the population of Lewiston was 34,203, up from 31,894 in 2010.

Lewiston is located at the confluence of the Snake River and Clearwater River, thirty miles (50 km) upstream and southeast of the Lower Granite Dam. Dams and locks on the Snake and Columbia Rivers make Lewiston reachable by some ocean-going vessels. The Port of Lewiston is Idaho's only seaport, and is the farthest inland port linked to the Pacific Ocean. The Lewiston-Nez Perce County Airport serves the city by air.