The Colorado River runs mostly tamely as it winds through Moab, the gateway city to the stunning red-rock formations of Arches and Canyonlands national parks and other archeologically rich areas near the Colorado border in the western U.S. state of Utah. But along its 1,450-mile course from the high Colorado mountains to Mexico's Sea of Cortez, its raging rapids cut some of North America's most famous and forbidding canyons, including the Grand Canyon in Arizona. Photo by Carol Highsmith, 2022.