The Grand Canyon is one of the most remarkable natural wonders in the world. Located in the state of Arizona, USA, it is one of the deepest gorges on Earth with an average depth of one mile (1.6km) and an average width of ten miles. The canyon was carved over the past 6 million years by the action of the Colorado River as it drops over 2,200 feet along the 277-mile length of the gorge. 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.