Canyons of the Colorado

John Wesley Powell (1834–1902) was a distinguished U.S. soldier, geologist, explorer of the American West, and prolific writer. Most renowned for his daring exploratory trips down the Green and Colorado Rivers in 1869 and 1871, Powell is also lauded for his profound contributions to the understanding of the geology and geography of the western United States. His scholarly work has left an indelibl...