Colorado River as 2 billion years. The of the river that flow through the Grand Canyon are largely encompassed by Grand Canyon National Park and are known for their difficult whitewater, separated by pools that reach up to in depth. At the lower end of Grand Canyon, the Colorado widens into Lake Mead, the largest reservoir in the continental United States, formed by Hoover Dam on the border of Arizona and Nevada. Situated southeast of metropolitan Las Vegas, the dam is an integral component for management of the Colorado River, controlling floods and storing water for farms and cities in the lower
Steamboats of the Colorado River shared information about the conditions on the river above them. Robinson piloted the "Explorer" above the point reached by Johnson into the Black Canyon of the Colorado, where they struck a rock that damaged the boat, 40 miles above where Johnson reached. Ives named that rock "Explorer's Rock". While the "Explorer" was being repaired by his engineer, Ives, Robinson and the boat's mate, took their skiff over the next two days farther up the river exploring up through the Black Canyon and beyond to the vicinity of Fortification Rock. Next day, they went two miles farther to Las Vegas Wash,