Grand Canyon National Park is the United States' 15th oldest national park. The park's central feature is the Grand Canyon, a gorge of the Colorado River, which is often considered one of the Seven Natural Wonders of the World. The park covers 1,217,262 acres (1,902 sq mi; 4,926 km2) of unincorporated area in Coconino and Mohave counties.
The Grand Canyon is 277 miles (446 km) long, up to 18 miles (29 km) wide and attains a depth of over a mile (6,000 feet / 1,800 metres).. Nearly two billion years of the 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 the specific geologic processes and timing that formed the Grand Canyon are the subject of debate by geologists, recent evidence suggests the Colorado River established its course through the canyon at least 17 million years ago. Since that time, the Colorado River continued to erode and form the canyon to its present-day configuration.
Wikipedia.org
Property No #75
Date of Inscription on the List of UNESCO: 1979
Thank you, Meeli !
Sent on: August 8, 2012
Received on: August 14, 2012
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