The Grand Canyon is a steep-sided canyon carved by the Colorado River in the United States in the state of Arizona. This is the most spectacular gorge in the world, carved by the Colorado river. It is largely contained within the Grand Canyon National Park, one of the first national parks in the United States.
The Grand Canyon is 277 miles (446 km) long, up to 18 miles (29 km) wide and (6,000 feet / 1,800 metres)deep.
Grand Canyon National Park is one of the world’s premier natural attractions, attracting about five million visitors per year. It was enlisted as the UNESCO World Heritage site in 1979.
Sources, related links:
http://www.nps.gov/grca/index.htm
http://www.unep-wcmc-apps.org/sites/wh/pdf/Grand%20Canyon.pdf
