Interstate 5 (I-5) is the main north–south Interstate Highway on the West Coast of the United States, running largely parallel to the Pacific coast of the contiguous U.S. from Mexico to Canada. It travels through the states of California, Oregon, and Washington, serving several large cities on the West Coast, including San Diego, Los Angeles, Sacramento, Portland, and Seattle. It is the only continuous Interstate highway to touch both the Mexican and Canadian borders. Upon crossing the Mexican border at its southern terminus, the highway continues to Tijuana, Baja California, as Mexican Federal Highway 1 (Fed. 1). Upon crossing the Canadian border at its northern terminus, it continues to Vancouver as British Columbia Highway 99 (BC 99).
Siskiyou County is a county located in the northwestern portion of the U.S. state of California. As of the 2020 census, the population was 44,076. Its county seat is Yreka and its highest point is Mount Shasta. It falls within the Cascadia bioregion.
Dunsmuir is a city in Siskiyou County, northern California. It is on the upper Sacramento River. Its population is 1,707 as of the 2020 census, up from 1,650 from the 2010 census.
Pacific Highway is the name of several north–south highways in the Pacific Coast region of the Western United States, either by legislation officially designating it as such or by common usage.
U.S. Route 99 (US 99) was a main north–south United States Numbered Highway on the West Coast of the United States until 1964, running from Calexico, California, on the Mexican border to Blaine, Washington, on the Canadian border. It was assigned in 1926 and existed until it was replaced for the most part by Interstate 5. Known also as the "Golden State Highway" and "The Main Street of California", US 99 was important throughout much of the 1930s as a route for Dust Bowl immigrant farm workers to traverse the state. Large portions are now California State Route 99 (SR 99), Oregon's Routes 99, 99W, and 99E, and Washington's SR 99. The highway in Washington connected to British Columbia Highway 99, whose number was derived from that of US 99, at the Canada–US border.
The Siskiyou Mountains are a coastal subrange of the Klamath Mountains, and located in northwestern California and southwestern Oregon in the United States. They extend in an arc for approximately 100 miles (160 km) from east of Crescent City, California, northeast along the north side of the Klamath River into Josephine and Jackson counties in Oregon. The mountain range forms a barrier between the watersheds of the Klamath River to the south and the Rogue River to the north. Accordingly, much of the range is within the Rogue River – Siskiyou and Klamath national forests, and the Pacific Crest Trail follows a portion of the crest of the Siskiyous.
Donner Pass is a 7,056-foot-high (2,151 m) mountain pass in the northern Sierra Nevada, above Donner Lake and Donner Memorial State Park about 9 miles (14 km) west of Truckee, California. Like the Sierra Nevada themselves, the pass has a steep approach from the east and a gradual approach from the west.
The Siskiyou Trail stretched from California's Central Valley to the Columbia River in Washington State; modern-day Interstate 5 follows this pioneer path. Originally based on existing Native American foot trails winding their way through river valleys, the Siskiyou Trail provided the shortest practical travel path between early settlements in California and Oregon.
The Central Oregon & Pacific Railroad is a Class II railroad operating between Northern California and Eugene, Oregon, United States. It was previously a mainline owned by the Southern Pacific Railroad (SP) between Eugene and Weed, California via Medford, Oregon. SP sold the route on December 31, 1994, in favor of using its route to Eugene via Klamath Falls, Oregon and Cascade Summit.
Oregon Route 58, also known as the Willamette Highway No. 18, is a state highway in the U.S. state of Oregon. The route, signed east–west, runs in a southeast–northwest direction, connecting U.S. Route 97 north of Chemult with Interstate 5 south of Eugene. It links the Willamette Valley and Central Oregon, crossing the Cascade Range at Willamette Pass. OR 58 is generally a modern two-lane highway with a speed limit of 55 mph (88 km/h), built through the Willamette National Forest in the 1930s.
Siskiyou Pass is a historic mountain pass in the Siskiyou Mountains of Jackson County in the U.S. state of Oregon. It is the most used pass in Oregon. The Hudson's Bay Company (HBC) made the Siskiyou Trail over the pass before pioneers traversed it with their wagons, while still later it evolved into a stage road, a railroad line, and a highway route. The name Siskiyou is believed to be derived from Cree, meaning "bob-tailed horse". Siskiyou Pass is west of the summit of Interstate 5, which is known as Siskiyou Summit.
Interstate 80 (I-80) traverses the northern portion of the US state of Nevada. The freeway serves the Reno metropolitan area and passes through the towns of Fernley, Lovelock, Winnemucca, Battle Mountain, Carlin, Elko, Wells, and West Wendover on its way through the state.
The Siskiyou Wilderness is a federal wilderness area designated by the passage of the California Wilderness Act of 1984. Originally, the land area was 153,000 acres (620 km2) The Northern California Wild Heritage Act of 2006 added 30,122 acres (121.90 km2) for the current total of 182,802 acres (739.77 km2). All of the wilderness is in Northern California and is managed by the U.S. Forest Service. The wilderness spans three national forests: the Rogue River–Siskiyou, the Klamath, and the Six Rivers.
Black Butte is a cluster of overlapping dacite lava domes in a butte, a satellite cone of Mount Shasta. It is located directly adjacent to the northbound lanes of Interstate 5 at milepost 742 between the cities of Mount Shasta and Weed, California. The I-5 freeway crosses a 3,912 ft (1,192 m) pass, Black Butte Summit, at the western base of the lava domes. The lava domes were extruded at the foot of the cone of Shastina following the period of its major eruptions about 9,000–10,000 years ago.
Interstate 5 (I-5) is a major north–south route of the Interstate Highway System in the United States, running largely parallel to the Pacific Coast between the Mexican border and the Canadian border. The segment of I-5 in California runs across the length of the state from the Mexican border at the San Ysidro Port of Entry in the San Ysidro neighborhood of San Diego to the Oregon state line south of the Medford-Ashland metropolitan area. It is the longest interstate in California at 796.77 miles (1,282.28 km), and accounts for more than half of I-5's total length of 1,381.29 miles (2,222.97 km). It is also the second longest stretch of Interstate Highway with a single designation within a single state after I-10 in Texas.
Interstate 80 (I-80) is a part of the Interstate Highway System that runs from San Francisco, California, to Teaneck, New Jersey. The portion of the highway in the US state of Utah is 197.51 miles (317.86 km) long through the northern part of the state. From west to east, I-80 crosses the state line from Nevada in Tooele County and traverses the Bonneville Salt Flats—which are a part of the larger Great Salt Lake Desert. It continues alongside the Wendover Cut-off—the corridor of the former Victory Highway—US Route 40 (US-40) and the Western Pacific Railroad Feather River Route. After passing the Oquirrh Mountains, I-80 enters the Salt Lake Valley and Salt Lake County. A short portion of the freeway is concurrent with I-15 through Downtown Salt Lake City. At the Spaghetti Bowl, I-80 turns east again into the mouth of Parleys Canyon and Summit County, travels through the mountain range, and intersects the eastern end of I-84 near Echo Reservoir before turning northeast toward the Wyoming border near Evanston. I-80 was built along the corridor of the Lincoln Highway and the Mormon Trail through the Wasatch Range. The easternmost section also follows the historical routes of the first transcontinental railroad and US-30S.
Interstate 5 (I-5) in the U.S. state of Oregon is a major Interstate Highway that traverses the state from north to south. It travels to the west of the Cascade Mountains, connecting Portland to Salem, Eugene, Medford, and other major cities in the Willamette Valley and across the northern Siskiyou Mountains. The highway runs 308 miles (496 km) from the California state line near Ashland to the Washington state line in northern Portland, forming the central part of Interstate 5's route between Mexico and Canada.
Interstate 84 (I-84) in the U.S. state of Oregon is a major Interstate Highway that traverses the state from west to east. It is concurrent with U.S. Route 30 (US 30) for most of its length and runs 376 miles (605 km) from an interchange with I-5 in Portland to the Idaho state line near Ontario. The highway roughly follows the Columbia River and historic Oregon Trail in northeastern Oregon, and is designated as part of Columbia River Highway No. 2 and all of the Old Oregon Trail Highway No. 6; the entire length is also designated as the Vietnam Veterans Memorial Highway. I-84 intersects several of the state's main north–south roads, including US 97, US 197, I-82, and US 395.
U.S. Route 395 (US 395) is a United States Numbered Highway, stretching from Hesperia, California to the Canadian border in Laurier, Washington. The California portion of US 395 is a 557-mile (896 km) route which traverses from Interstate 15 (I-15) in Hesperia, north to the Oregon state line in Modoc County near Goose Lake. The route clips into Nevada, serving the cities Carson City and Reno, before returning to California.
The Rogue Valley Terminal Railroad is a 14-mile (23 km) shortline railroad that connects the industrial park in White City, Oregon, United States to the Central Oregon and Pacific Railroad, which hauls its cars to the Union Pacific Railroad at Eugene, Oregon or Black Butte, California via the Siskiyou Summit, or to the Yreka Western Railroad at Montague, California.
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