The Columbia River 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 volume, the Columbia has the greatest flow of any river entering the Pacific outside of Asia, and the 36th greatest discharge of any river in the world.
Mount St. Helens is an active stratovolcano located in Skamania County, Washington, in the Pacific Northwest region of the United States. It lies 52 miles (83 km) northeast of Portland, Oregon, and 98 miles (158 km) south of Seattle. Mount St. Helens takes its English name from that of the British diplomat Alleyne Fitzherbert, 1st Baron St Helens, a friend of explorer George Vancouver who surveyed the area in the late 18th century. The volcano is part of the Cascade Volcanic Arc, a segment of the Pacific Ring of Fire.
The Cascade Range or Cascades is a major mountain range of western North America, extending from southern British Columbia through Washington and Oregon to Northern California. It includes both non-volcanic mountains, such as many of those in the North Cascades, and the notable volcanoes known as the High Cascades. The small part of the range in British Columbia is referred to as the Canadian Cascades or, locally, as the Cascade Mountains. The highest peak in the range is Mount Rainier in Washington at 14,411 feet (4,392 m).
Cascade Locks is a city in Hood River County, Oregon, United States. The city got its name from a set of locks built to improve navigation past the Cascades Rapids of the Columbia River. The U.S. federal government approved the plan for the locks in 1875, construction began in 1878, and the locks were completed on November 5, 1896. The locks were subsequently submerged in 1938, replaced by Bonneville Lock and Dam, although the city did not lose land from the expansion of Lake Bonneville behind the dam some 4 miles (6 km) downstream of the city. The city population was 1,144 at the 2010 census.
Mount Hood is an active stratovolcano in the Cascade Volcanic Arc. It was formed by a subduction zone on the Pacific coast and rests in the Pacific Northwest region of the United States. It is located about 50 mi (80 km) east-southeast of Portland, on the border between Clackamas and Hood River counties. In addition to being Oregon's highest mountain, it is one of the loftiest mountains in the nation based on its prominence, and it offers the only year-round lift-served skiing in North America.
The Columbia River Gorge is a canyon of the Columbia River in the Pacific Northwest of the United States. Up to 4,000 feet (1,200 m) deep, the canyon stretches for over eighty miles (130 km) as the river winds westward through the Cascade Range, forming the boundary between the state of Washington to the north and Oregon to the south. Extending roughly from the confluence of the Columbia with the Deschutes River in the east down to the eastern reaches of the Portland metropolitan area, the water gap furnishes the only navigable route through the Cascades and the only water connection between the Columbia Plateau and the Pacific Ocean. It is thus that the routes of Interstate 84, U.S. Route 30, Washington State Route 14, and railroad tracks on both sides run through the gorge.
Mount Adams, known by some Native American tribes as Pahto or Klickitat, is a potentially active stratovolcano in the Cascade Range. Although Adams has not erupted in more than 1,000 years, it is not considered extinct. It is the second-highest mountain in Washington, after Mount Rainier.
The 1700 Cascadia earthquake occurred along the Cascadia subduction zone on January 26, 1700, with an estimated moment magnitude of 8.7–9.2. The megathrust earthquake involved the Juan de Fuca Plate from mid-Vancouver Island, south along the Pacific Northwest coast as far as northern California. The plate slipped an average of 20 meters (66 ft) along a fault rupture about 1,000 kilometers long.
The Cascades Rapids were an area of rapids along North America's Columbia River, between the U.S. states of Washington and Oregon. Through a stretch approximately 150 yards (140 m) wide, the river dropped about 40 feet (12 m) in 2 miles (3.2 km). These rapids or cascades, along with the many cascades along the Columbia River Gorge in this area of Oregon and Washington, gave rise to the name for the surrounding mountains: the Cascade Range.
The Cascadia subduction zone is a 960 km (600 mi) fault at a convergent plate boundary, about 100–200 km (70–100 mi) off the Pacific coast, that stretches from northern Vancouver Island in Canada to Northern California in the United States. It is capable of producing 9.0+ magnitude earthquakes and tsunamis that could reach 30 m (98 ft). The Oregon Department of Emergency Management estimates shaking would last 5–7 minutes along the coast, with strength and intensity decreasing further from the epicenter. It is a very long, sloping subduction zone where the Explorer, Juan de Fuca, and Gorda plates move to the east and slide below the much larger mostly continental North American Plate. The zone varies in width and lies offshore beginning near Cape Mendocino, Northern California, passing through Oregon and Washington, and terminating at about Vancouver Island in British Columbia.
The Bridge of the Gods is a steel truss cantilever bridge that spans the Columbia River between Cascade Locks, Oregon, and Washington state near North Bonneville. It is approximately 40 miles (64 km) east of Portland, Oregon, and 4 miles (6.4 km) upriver from Bonneville Dam. It is a toll bridge operated by the Port of Cascade Locks.
Table Mountain is a peak rising on the north side of the Columbia River in Washington state, about 4 miles (6.4 km) north-northwest of Bonneville Dam. It is one of the most spectacular landmarks of the Columbia River Gorge. Its southeast face drops 2,400 feet (730 m) in less than one horizontal mile (1.6 km.), and is topped by an almost vertical 800-foot (240 m) cliff. Table Mountain is joined by the similar Greenleaf Peak to the northeast, and also by Hamilton Mountain to the southwest, which is lower,, but similarly steep and much closer to the Columbia. Together these peaks form an impressive group on the Washington side of the Gorge.
The Mount Meager massif is a group of volcanic peaks in the Pacific Ranges of the Coast Mountains in southwestern British Columbia, Canada. Part of the Cascade Volcanic Arc of western North America, it is located 150 km (93 mi) north of Vancouver at the northern end of the Pemberton Valley and reaches a maximum elevation of 2,680 m (8,790 ft). The massif is capped by several eroded volcanic edifices, including lava domes, volcanic plugs and overlapping piles of lava flows; these form at least six major summits including Mount Meager which is the second highest of the massif.
The Cascade Volcanoes are a number of volcanoes in a volcanic arc in western North America, extending from southwestern British Columbia through Washington and Oregon to Northern California, a distance of well over 700 miles (1,100 km). The arc formed due to subduction along the Cascadia subduction zone. Although taking its name from the Cascade Range, this term is a geologic grouping rather than a geographic one, and the Cascade Volcanoes extend north into the Coast Mountains, past the Fraser River which is the northward limit of the Cascade Range proper.
The geology of the Pacific Northwest includes the composition, structure, physical properties and the processes that shape the Pacific Northwest region of North America. The region is part of the Ring of Fire: the subduction of the Pacific and Farallon Plates under the North American Plate is responsible for many of the area's scenic features as well as some of its hazards, such as volcanoes, earthquakes, and landslides.
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.
Greenleaf Peak is a mountain in the Cascade Range in the U.S. state of Washington, located on the north side of the Columbia River near Table Mountain, in the Columbia River Gorge. The peak lies within the Columbia River Gorge National Scenic Area near Bonneville Dam. It is 3,424 feet (1,044 m) in elevation. Botanist David Douglas climbed to the summit in September 1825, making this the first recorded mountain ascent in what is now Washington state.
Dodson is an unincorporated community in Multnomah County, Oregon, United States. It is located about 4½ miles (7.2 km) east of Multnomah Falls and one mile west of Warrendale, in the Columbia River Gorge on Interstate 84/U.S. Route 30. It is across the Columbia River from Skamania, Washington. Dodson is within the Cascade Locks ZIP code.
Warrendale is an unincorporated community in Multnomah County, Oregon, United States. It is located about a mile east of Dodson and about 3 miles (4.8 km) west of Bonneville in the Columbia River Gorge on Interstate 84/U.S. Route 30. It is across the Columbia River from Beacon Rock. The community was the site of an important salmon cannery founded in the 1870s.
Frederic Homer Balch (1861—1891) was an American author from the Pacific Northwest, best known for The Bridge of the Gods: A Romance of Indian Oregon, the only work published during his brief life. Balch was the first Northwest writer to make Native Americans major characters and the first to celebrate the Northwest landscape, its primal forest, great rivers, and volcanic mountains.
