Instruct: Given a question, retrieve documents that answer the question.
Query: Where is the deepest canyon in the United States?
No roads cross Hells Canyon and only three roads reach the Snake River between Hells Canyon Dam and the Oregon–Washington state boundary further downstream. From Oxbow Bridge near Copperfield, Oregon, Hells Canyon Road follows the Idaho side of the river downstream to the Hells Canyon Dam. The road crosses the dam and continues another mile to the Hells Canyon Visitor Center on the Oregon side. Further north on the Idaho side, Deer Creek Road connects White Bird, Idaho, to the river at Pittsburg Landing. Near the northern end of the canyon, Forest Road 4260 (Lower Imnaha Road), the last part of which is too rough for most cars, reaches the river at Dug Bar, from Imnaha, Oregon. On the canyon rims, viewpoints accessible by road include Hat Point and Buckhorn in Oregon and Heavens Gate in Idaho.
The Tropical Andes are located in South America following the path of the Andes. They run, mainly, through five countries, Venezuela, Colombia, Ecuador, Peru, and Bolivia. The land initially was roughly but has decreased to , leaving 25% of the original land. Due to the massive amount of area the landscape is diverse. Diverse landscapes lead to diverse habitats and the ability to provide needed resources for many species. The diverse landscape includes snow-topped mountains down to canyons and valleys. The different vegetation as altitude changes includes tropical rainforests at , cloud forests ranging from , and the highest altitudes of contain grasslands up to snow. The most diverse cloud forests found in Peru and Bolivia covers . Dry forests and woodlands are also found throughout the Tropical Andes. The range is also home to the deepest gorge in Peru at deep and Lake Titicaca, the highest navigable water with an altitude of .
The Arun River enters from Tibet at an elevation of about 3,500 meters (11,500 feet) and flows south across the district, forming one of the world's deepest valleys relative to 8,481 meter Makalu to the west and 8,586 meter Kangchenjunga to the east.
Trieste is a Swiss-designed, Italian-built deep-diving research bathyscaphe, which with its crew of two reached a record maximum depth of about , in the deepest known part of the Earth's oceans, the Challenger Deep, in the Mariana Trench near Guam in the Pacific. On 23 January 1960, Jacques Piccard (son of the boat's designer Auguste Piccard) and US Navy Lieutenant Don Walsh achieved the goal of Project Nekton.
There are many examples of chalk dry valleys along the North and South Downs in southern England. Notably the National Trust-owned Devil's Dyke near Brighton covers some of downland scarp, and includes the deepest dry valley in the world – created when melting water eroded the chalk downland to the permafrost layer after the last ice age. The three-quarter mile long curved dry valley is around in height and attracts tourists with its views of Sussex, Hampshire and Kent.
About two-thirds of Florida occupies a peninsula between the Gulf of Mexico and the Atlantic Ocean. Florida has the longest coastline in the contiguous United States, approximately , not including the contribution of the many barrier islands. Florida has a total of 4,510 islands that are ten acres or larger in area. This is the second-highest number of islands of any state of the United States; only Alaska has more. It is the only state that borders both the Gulf of Mexico and the Atlantic Ocean. Much of the state is at or near sea level and is characterized by sedimentary soil. Florida has the lowest high point of any U.S. state. The climate varies from subtropical in the north to tropical in the south. The American alligator, American crocodile, American flamingo, Roseate spoonbill, Florida panther, bottlenose dolphin, and manatee can be found in Everglades National Park in the southern part of the state. Along with Hawaii, Florida is one of only two states that has a tropical climate, and is the only continental state with either a tropical climate or a coral reef. The Florida Reef is the only living coral barrier reef in the continental United States, and the third-largest coral barrier reef system in the world (after the Great Barrier Reef and Belize Barrier Reef).
Navajo County offers not only the Monument Valley, but Keams Canyon, part of the Petrified Forest National Park, and one of the largest contiguous ponderosa pine forest in North America. Navajo County has of federally designated Indian reservation within its borders, the third most of any county in the United States (neighboring Apache County and Coconino County are first and second). In descending order of territory within the county, the reservations are the Navajo Nation, Hopi Indian Reservation, and Fort Apache Indian Reservation, all of which are partly located within Navajo County.As of the 2000 census, there were 97,470 people, 30,043 households, and 23,073 families residing in the county. The population density was 10 people per square mile (4/km²). There were 47,413 housing units at an average density of 5 per square mile (2/km²). The racial makeup of the county was 47.74% Native American, 45.91% White, 0.88% Black or African American, 0.33% Asian, 0.05% Pacific Islander, 3.15% from other races, and 55.94% from two or more races. 8.22% of the population were Hispanic or Latino of any race. 24.77% reported speaking Navajo at home, 5.94% other Southern Athabaskan languages, 4.71% Spanish, and 3.23% Hopi.
The caves and rock shelters vary in size and what they contain. Many contain paintings and other forms of graphic representation. Contents include ceramics and stone tools. The corn materials show similarities to the first vestiges of the domestication of wheat and rye in the Middle East. One of the deepest caves is called the Cueva de la Paloma. The caves have been studied since the 1960s, especially the Cueva de Guilá Naquitz (white stone in Zapotec), which has some of the best evidence for the domestication of corn and squash, which dates back more than 10,000 years. Other caves, such as those near Yagual and Mitla confirm findings at Guilá Naquitz and show human occupation to about 8000 years BCE the sites also show similarities to the Head Smashed and Buffalo Jump Complex sites in Canada. Many more smaller caves with similar artifacts are thought to exist in the area.
Sea urchins are established in most seabed habitats from the intertidal downwards, at an extremely wide range of depths. Some species, such as "Cidaris abyssicola", can live at depths of several thousands metres. Many genera are only found in the abyssal zone, including many cidaroids, most of the genera in the Echinothuriidae family, and the "cactus urchins" "Dermechinus". One of the deepest-living families is the "Pourtalesiidae", strange bottle-shaped irregular sea urchins that live only in the hadal zone and have been collected as deep as 6850 metres beneath the surface in the Sunda Trench. Nevertheless, this makes sea urchin the class of echinoderms living the least deep, compared to brittle stars, starfish and crinoids that remain abundant below and sea cucumbers which have been recorded from .
The rock is a large rounded monolith of Archean granite typical of the surrounding region and is an isolated peak at the southeast end of the Granite Mountains. Its appearance is somewhat like the rounded Enchanted Rock of Texas or Uluru in Australia (formerly known as Ayers Rock), although smaller in size. It is located in the high plateau region of central Wyoming, north of the Sentinel Rocks ridge and adjacent to the Sweetwater River. It is accessible from a rest area on Wyoming Highway 220, approximately northeast of Muddy Gap and south-west of Casper.
The northern end is about from the northern end of the Grand Junction Canal at Braunston, Northamptonshire and the southern end about .
At 3,076 yards (2,813m) long it is the third-longest navigable canal tunnel on the UK canal network after Standedge Tunnel and Dudley Tunnel (and the ninth-longest canal tunnel in the world). At its deepest point it is "ca."143 feet ("ca."43m) below ground level.
The Blue Hole is an attraction on the island of Big Pine Key in the Florida Keys. It is an abandoned rock quarry that was used for nearby road fills and Henry Flagler's Overseas Railroad. The water it contains is mostly fresh and is used by various wildlife in the area, such as birds, snakes, alligators, key deer and green iguanas. It is part of the National Key Deer Refuge.
Lake Tali Karng is a natural lake in the Alpine region of Victoria, in eastern Australia. At in area and in depth, the lake is the only deep lake in Victoria. The lake was formed by a landslide 1,500 years ago and is the only lake in the Alpine region.
The American River is fed by its North, Middle, and South forks, which are located in El Dorado County, Placer County, and Sacramento County. The river's three forks originate in the Tahoe and Eldorado National Forests. The North and Middle Forks join near Auburn, and continue downstream as the North Fork, although the Middle Fork carries a higher volume of water. The North and South Forks join in Folsom Lake. All three forks are known for their verdant canyons, forested ridges, massive rock formations, trails, backcountry winter adventuring among snowy peaks, fishing and white water rafting. There are various fish species that live within the American River such as Chinook Salmon and Steelhead Trout.
In terms of area covered, the largest lake in California is the Salton Sea, a lake formed in 1905 which is now saline. It occupies in the southeast corner of the state, but because it is shallow it only holds about of water. Tulare Lake in the San Joaquin Valley was larger, at approximately , until it was drained during the later years of the nineteenth century.
The Blue Hole is a fresh water pond located in Castalia, Erie County, Ohio, in the United States. From the 1920s to 1990 the Blue Hole was a tourist site, attracting 165,000 visitors annually at the height of its popularity, partly because of its location on State Route 269, about southwest of the Cedar Point amusement park in Sandusky, Ohio.
Yellowstone National Park spans an area of , comprising lakes, canyons, rivers and mountain ranges. Yellowstone Lake is one of the largest high-elevation lakes in North America and is centered over the Yellowstone Caldera, the largest supervolcano on the continent. The caldera is considered an active volcano. It has erupted with tremendous force several times in the last two million years. Half of the world's geysers and hydrothermal features are in Yellowstone, fueled by this ongoing volcanism. Lava flows and rocks from volcanic eruptions cover most of the land area of Yellowstone. The park is the centerpiece of the Greater Yellowstone Ecosystem, the largest remaining nearly-intact ecosystem in the Earth's northern temperate zone. In 1978, Yellowstone was named a UNESCO World Heritage Site.
Of the 120 known indigenous snake species in North America, only 20 are venomous to human beings, all belonging to the families Viperidae and Elapidae. However, in the United States, every state except Maine, Alaska, and Hawaii is home to at least one of 20 venomous snake species. Up to 95% of all snakebite-related deaths in the United States are attributed to the western and eastern diamondback rattlesnakes. Further, the majority of bites in the United States occur in the southwestern part of the country, in part because rattlesnake populations in the eastern states are much lower.
The American River watershed crosses multiple climate zones due to the large range in elevations. The climate of the lower American River valley is Mediterranean and temperate grassland. Sacramento County in particular, where the main stem American River is located, is known for its cool winters and hot summers, with low average precipitation. The North, Middle and South Forks originate in alpine zones along the Sierra Crest and flow through subalpine, montane and temperate coniferous forests. In the foothills, oak woodland and grassland are dominant.
Yellowstone National Park has one of the world's largest petrified forests, trees which were long ago buried by ash and soil and transformed from wood to mineral materials. This ash and other volcanic debris are believed to have come from the park area itself as the central part of Yellowstone is the massive caldera of a supervolcano. The park contains 290 waterfalls of at least , the highest being the Lower Falls of the Yellowstone River at .
At the Hood Canal, US 101 follows the western shore to SR 106, where it turns directly south to the east end of SR 106 and Shelton, to meet the west end of SR 3. After some time going south, US 101 meets SR 108, the second-to-last major junction. After going southeast, US 101 finally joins SR 8 and turns into a freeway to its easternmost point of US 101 in Washington, the so-called "north end" at I-5 near Tumwater.
The Buckskin Gulch, a canyon in southern Utah, is one of the main tributaries of the Paria River, which is itself a minor tributary of the Colorado River. It is the longest and deepest slot canyon in the southwest United States and may be the longest in the world. As such it is one of the premier destinations for slot canyon hikers, and receives a high amount of foot traffic.
Neffs Cave (or Neffs Canyon Cave) is a cave in Neffs Canyon on the north side of Mount Olympus, Utah, in the United States. It is one of the deepest caves in the United States but is seldom entered despite its depth and its proximity to Salt Lake City, Utah. The United States Forest Service has closed the cave to the public for many years due to safety hazards.
The Yarlung Tsangpo Grand Canyon (or Tsangpo Canyon), along the Yarlung Tsangpo River in Tibet, is regarded by some as the deepest canyon in the world at 5,500 m (18,000 ft). It is slightly longer than the Grand Canyon in the United States. Others consider the Kali Gandaki Gorge in midwest Nepal to be the deepest canyon, with a 6400 m (21,000 ft) difference between the level of the river and the peaks surrounding it.
The cave is a solutional cave formed in Mesozoic marble (metamorphosed limestone). It is a cave with many varieties of natural speleothems, including rare "shield" formations. Boyden Cave or Boyden Cavern is located in the deepest river cut canyon of the United States, the deep Kings Canyon. The cave entrance lies beneath the high marble walls of the famous Portals of the Kings, near the Kings River.