Top-Rated Tourist Attractions in the USA
The United States is home to some of the most spectacular scenery in the world and some of the most recognizable icons on the planet. Many of the top attractions in the United States are bucket list destinations, drawing visitors from around the world.
Grand Canyon
The canyon and adjacent rim are contained within Grand Canyon National Park, the Kaibab National Forest, the Grand Canyon–Parashant National Monument, the Hualapai Indian Reservation, the Havasupai Indian Reservation, and the Navajo Nation. The surrounding area is contained within the Baaj Nwaavjo I'tah Kukveni – Ancestral Footprints of the Grand Canyon National Monument. President Theodore Roosevelt was a major proponent of the preservation of the Grand Canyon area and visited it on numerous occasions to hunt and enjoy the scenery.
Nearly two billion years of Earth's geological history have been exposed as the Colorado River and its tributaries cut their channels through layer after layer of rock while the Colorado Plateau was uplifted. While some aspects about the history of incision of the canyon are debated by geologists, several recent studies support the hypothesis that the Colorado River established its course through the area about 5 to 6 million years ago. Since that time, the Colorado River has driven the down-cutting of the tributaries and retreat of the cliffs, simultaneously deepening and widening the canyon.
For thousands of years, the area has been continuously inhabited by Native Americans, who built settlements within the canyon and its many caves. The Pueblo people considered the Grand Canyon a holy site and made pilgrimages to it. The first European known to have viewed the Grand Canyon was García López de Cárdenas from Spain, who arrived in 1540.
Geography
The Grand Canyon is a river valley in the Colorado Plateau that exposes uplifted Proterozoic and Paleozoic strata, and it is also one of the six distinct physiographic sections of the Colorado Plateau province. Even though it is not the deepest canyon in the world (Kali Gandaki Gorge in Nepal is much deeper), the Grand Canyon is known for its visually overwhelming size and its intricate and colorful landscape. Geologically, it is significant because of the thick sequence of ancient rocks that are well preserved and exposed in the walls of the canyon. These rock layers record much of the early geologic history of the North American continent.
Uplift associated with mountain formation later moved these sediments thousands of feet upward and created the Colorado Plateau. The higher elevation has also resulted in greater precipitation in the Colorado River drainage area, but not enough to change the Grand Canyon area from being semi-arid. The uplift of the Colorado Plateau is uneven, and the Kaibab Plateau that the Grand Canyon bisects is over one thousand feet (300 m) higher at the North Rim than at the South Rim. Almost all runoff from the North Rim (which also gets more rain and snow) flows toward the Grand Canyon, while much of the runoff on the plateau behind the South Rim flows away from the canyon (following the general tilt). The result is deeper and longer tributary washes and canyons on the north side and shorter and steeper side canyons on the south side.
Temperatures on the North Rim are generally lower than those on the South Rim because of the greater elevation (averaging 8,000 feet or 2,400 meters above sea level). Heavy rains are common on both rims during the summer months. Access to the North Rim via the primary route leading to the canyon (State Route 67) is limited during the winter season due to road closures.
Geology
The Grand Canyon is part of the Colorado River basin, which has developed over the past 70 million years. Over more than 150 years, scientists have gathered data, proposed new ideas, and debated sometimes contentious theories about the geologic origins of the Grand Canyon and the Colorado River. The formation of the Grand Canyon and the Colorado River may involve a complex history in which multiple factors and geologic processes have interacted over time and in different locations.
In the most recent round of the "old river" vs. "young river" controversy, researchers have challenged estimates that had placed the age of the canyon at 5–6 million years. The research has aroused considerable controversy because it suggests a substantial departure from prior widely supported scientific consensus.
In a 2008 study, Victor Polyak examined caves near the Grand Canyon and placed their origins about 17 million years ago. The study, which was published in the journal Science in 2008, used uranium-lead dating to analyze calcite deposits found on the walls of nine caves throughout the canyon.
In another 2008 study, Rebecca Flowers reported on apatite (U-Th)/He thermochronometry results suggesting that parts of the Grand Canyon had reached a depth near to the modern depth around 20 million years ago. In a subsequent study published in the journal Science in 2012, she suggested that the western part of the Grand Canyon could be as old as 70 million years.
The emerging scientific consensus is that the canyon is made up of multiple segments that formed at different times and eventually connected to become the waterway now traversed by the Colorado River. Of the three central segments, the "Hurricane" was formed 50–70 million years ago, and the "Eastern Grand Canyon" was cut 15–25 million years ago. In contrast, the "Marble Canyon" and "Westernmost Grand Canyon" segments at the ends of the canyon were carved in the last five to six million years.
The major geologic exposures in the Grand Canyon range in age from the two-billion-year-old Vishnu Schist at the bottom of the Inner Gorge to the 270-million-year-old Kaibab Limestone on the Rim. There is a gap of about a billion years between 1.75 billion and 1.25 billion years ago. This large unconformity indicates a long period for which no deposits are present.
Then, between 1.25 billion and 730 million years ago, intermittent sediments began to form the Grand Canyon Supergroup. Many of the formations were deposited in warm shallow seas, near-shore environments (such as beaches), and swamps as the seashore repeatedly advanced and retreated over the edge of a proto-North America. Major exceptions include the Permian Coconino Sandstone, which contains abundant geological evidence of aeolian sand dune deposition. Several parts of the Supai Group also were deposited in non-marine environments.
The great depth of the Grand Canyon and especially the height of its strata (most of which formed below sea level) can be attributed to 5,000–10,000 feet (1,500–3,000 m) of uplift of the Colorado Plateau, starting about 65 million years ago (during the Laramide orogeny). This uplift has steepened the stream gradient of the Colorado River and its tributaries, which in turn has increased their speed and thus their ability to cut through rock (see the elevation summary of the Colorado River for present conditions).
Weather conditions during the ice ages also increased the amount of water in the Colorado River drainage system. The ancestral Colorado River responded by cutting its channel faster and deeper.
The base level and course of the Colorado River (or its ancestral equivalent) changed 5.3 million years ago when the Gulf of California opened and lowered the river's base level (its lowest point). This increased the rate of erosion and cut nearly all of the Grand Canyon's current depth by 1.2 million years ago. The terraced walls of the canyon were created by differential erosion.
Between 100,000 and 3 million years ago, volcanic activity deposited ash and lava over the area, which at times completely obstructed the river. These volcanic rocks are the youngest in the canyon.
The Grand Canyon is a river valley in the Colorado Plateau that exposes uplifted Proterozoic and Paleozoic strata, and it is also one of the six distinct physiographic sections of the Colorado Plateau province. Even though it is not the deepest canyon in the world (Kali Gandaki Gorge in Nepal is much deeper), the Grand Canyon is known for its visually overwhelming size and its intricate and colorful landscape. Geologically, it is significant because of the thick sequence of ancient rocks that are well preserved and exposed in the walls of the canyon. These rock layers record much of the early geologic history of the North American continent.
Uplift associated with mountain formation later moved these sediments thousands of feet upward and created the Colorado Plateau. The higher elevation has also resulted in greater precipitation in the Colorado River drainage area, but not enough to change the Grand Canyon area from being semi-arid. The uplift of the Colorado Plateau is uneven, and the Kaibab Plateau that the Grand Canyon bisects is over one thousand feet (300 m) higher at the North Rim than at the South Rim. Almost all runoff from the North Rim (which also gets more rain and snow) flows toward the Grand Canyon, while much of the runoff on the plateau behind the South Rim flows away from the canyon (following the general tilt). The result is deeper and longer tributary washes and canyons on the north side and shorter and steeper side canyons on the south side.
Temperatures on the North Rim are generally lower than those on the South Rim because of the greater elevation (averaging 8,000 feet or 2,400 meters above sea level). Heavy rains are common on both rims during the summer months. Access to the North Rim via the primary route leading to the canyon (State Route 67) is limited during the winter season due to road closures.
Geology
The Grand Canyon is part of the Colorado River basin, which has developed over the past 70 million years. Over more than 150 years, scientists have gathered data, proposed new ideas, and debated sometimes contentious theories about the geologic origins of the Grand Canyon and the Colorado River. The formation of the Grand Canyon and the Colorado River may involve a complex history in which multiple factors and geologic processes have interacted over time and in different locations.
In the most recent round of the "old river" vs. "young river" controversy, researchers have challenged estimates that had placed the age of the canyon at 5–6 million years. The research has aroused considerable controversy because it suggests a substantial departure from prior widely supported scientific consensus.
In a 2008 study, Victor Polyak examined caves near the Grand Canyon and placed their origins about 17 million years ago. The study, which was published in the journal Science in 2008, used uranium-lead dating to analyze calcite deposits found on the walls of nine caves throughout the canyon.
In another 2008 study, Rebecca Flowers reported on apatite (U-Th)/He thermochronometry results suggesting that parts of the Grand Canyon had reached a depth near to the modern depth around 20 million years ago. In a subsequent study published in the journal Science in 2012, she suggested that the western part of the Grand Canyon could be as old as 70 million years.
The emerging scientific consensus is that the canyon is made up of multiple segments that formed at different times and eventually connected to become the waterway now traversed by the Colorado River. Of the three central segments, the "Hurricane" was formed 50–70 million years ago, and the "Eastern Grand Canyon" was cut 15–25 million years ago. In contrast, the "Marble Canyon" and "Westernmost Grand Canyon" segments at the ends of the canyon were carved in the last five to six million years.
The major geologic exposures in the Grand Canyon range in age from the two-billion-year-old Vishnu Schist at the bottom of the Inner Gorge to the 270-million-year-old Kaibab Limestone on the Rim. There is a gap of about a billion years between 1.75 billion and 1.25 billion years ago. This large unconformity indicates a long period for which no deposits are present.
Then, between 1.25 billion and 730 million years ago, intermittent sediments began to form the Grand Canyon Supergroup. Many of the formations were deposited in warm shallow seas, near-shore environments (such as beaches), and swamps as the seashore repeatedly advanced and retreated over the edge of a proto-North America. Major exceptions include the Permian Coconino Sandstone, which contains abundant geological evidence of aeolian sand dune deposition. Several parts of the Supai Group also were deposited in non-marine environments.
The great depth of the Grand Canyon and especially the height of its strata (most of which formed below sea level) can be attributed to 5,000–10,000 feet (1,500–3,000 m) of uplift of the Colorado Plateau, starting about 65 million years ago (during the Laramide orogeny). This uplift has steepened the stream gradient of the Colorado River and its tributaries, which in turn has increased their speed and thus their ability to cut through rock (see the elevation summary of the Colorado River for present conditions).
Weather conditions during the ice ages also increased the amount of water in the Colorado River drainage system. The ancestral Colorado River responded by cutting its channel faster and deeper.
The base level and course of the Colorado River (or its ancestral equivalent) changed 5.3 million years ago when the Gulf of California opened and lowered the river's base level (its lowest point). This increased the rate of erosion and cut nearly all of the Grand Canyon's current depth by 1.2 million years ago. The terraced walls of the canyon were created by differential erosion.
Between 100,000 and 3 million years ago, volcanic activity deposited ash and lava over the area, which at times completely obstructed the river. These volcanic rocks are the youngest in the canyon.
History
The known human history of the Grand Canyon area stretches back 10,500 years when the first evidence of human presence in the area was found. Native Americans have inhabited the Grand Canyon and the area now covered by Grand Canyon National Park for at least the last 4,000 of those years. Ancestral Pueblo peoples, first as the Basketmaker culture and later as the more familiar Pueblo people, developed from the Desert Culture as they became less nomadic and more dependent on agriculture. In a similar culture, the Cochimi also lived in the canyon area. Drought in the late 13th century likely caused both groups to move on. Other people followed, including the Paiute, Cerbat, and the Navajo, only to be later forced onto reservations by the United States Government.
In September 1540, under the direction of conquistador Francisco Vásquez de Coronado to find the fabled Seven Cities of Gold, Captain García López de Cárdenas led a party of Spanish soldiers with Hopi guides to the Grand Canyon. More than 200 years passed before two Spanish priests became the second party of non-Native Americans to see the canyon. U.S. Army Major John Wesley Powell led the 1869 Powell Geographic Expedition through the canyon on the Colorado River. This and later study by geologists uncovered the geology of the Grand Canyon area and helped to advance that science. In the late 19th century, the promise of mineral resources—mainly copper and asbestos—renewed interest in the region. The first pioneer settlements along the rim came in the 1880s.
Early residents soon realized that tourism was destined to be more profitable than mining, and by the turn of the 20th century, the Grand Canyon was a well-known tourist destination. Most visitors made the grueling trip from nearby towns to the South Rim by stagecoach. In 1901 the Grand Canyon Railway was opened from Williams, Arizona, to the South Rim, and the development of formal tourist facilities, especially at Grand Canyon Village, increased dramatically. The Fred Harvey Company developed many facilities at the Grand Canyon, including the luxury El Tovar Hotel on the South Rim in 1905 and Phantom Ranch in the Inner Gorge in 1922. Although first afforded federal protection in 1893 as a forest reserve and later as a U.S. National Monument, the Grand Canyon did not achieve U.S. National Park status until 1919, three years after the creation of the National Park Service. Today, Grand Canyon National Park receives about five million visitors yearly, a far cry from the annual visitation of 44,173 in 1919. (Wikipedia)
The known human history of the Grand Canyon area stretches back 10,500 years when the first evidence of human presence in the area was found. Native Americans have inhabited the Grand Canyon and the area now covered by Grand Canyon National Park for at least the last 4,000 of those years. Ancestral Pueblo peoples, first as the Basketmaker culture and later as the more familiar Pueblo people, developed from the Desert Culture as they became less nomadic and more dependent on agriculture. In a similar culture, the Cochimi also lived in the canyon area. Drought in the late 13th century likely caused both groups to move on. Other people followed, including the Paiute, Cerbat, and the Navajo, only to be later forced onto reservations by the United States Government.
In September 1540, under the direction of conquistador Francisco Vásquez de Coronado to find the fabled Seven Cities of Gold, Captain García López de Cárdenas led a party of Spanish soldiers with Hopi guides to the Grand Canyon. More than 200 years passed before two Spanish priests became the second party of non-Native Americans to see the canyon. U.S. Army Major John Wesley Powell led the 1869 Powell Geographic Expedition through the canyon on the Colorado River. This and later study by geologists uncovered the geology of the Grand Canyon area and helped to advance that science. In the late 19th century, the promise of mineral resources—mainly copper and asbestos—renewed interest in the region. The first pioneer settlements along the rim came in the 1880s.
Early residents soon realized that tourism was destined to be more profitable than mining, and by the turn of the 20th century, the Grand Canyon was a well-known tourist destination. Most visitors made the grueling trip from nearby towns to the South Rim by stagecoach. In 1901 the Grand Canyon Railway was opened from Williams, Arizona, to the South Rim, and the development of formal tourist facilities, especially at Grand Canyon Village, increased dramatically. The Fred Harvey Company developed many facilities at the Grand Canyon, including the luxury El Tovar Hotel on the South Rim in 1905 and Phantom Ranch in the Inner Gorge in 1922. Although first afforded federal protection in 1893 as a forest reserve and later as a U.S. National Monument, the Grand Canyon did not achieve U.S. National Park status until 1919, three years after the creation of the National Park Service. Today, Grand Canyon National Park receives about five million visitors yearly, a far cry from the annual visitation of 44,173 in 1919. (Wikipedia)
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