Palo Duro Canyon is located in the Texas panhandle and is part of the Caprock Escarpment, a term used in west Texas to describe the change of terrain from the high plains of the Llano Estacado to rolling hills. Nicknamed the "Grand Canyon of Texas," Palo Duro Canyon is about 120 miles long, about six miles wide and drops to about 800 feet at its deepest point. The canyon offers beautiful views of painted rock, trees and bushes about 25 miles southeast of Amarillo. The canyon was the site of the Red River War, which was a significant battle between the US Army and Comanche, Kiowa, Cheyenne and Arapahoe tribes in late 1874. The army launched a surprise attack, forcing Native Americans to seek protection in the hills. The battle lasted until early 1875 when tribes ran out of supplies and had to surrender. The war marked the end of Native Americans freely moving across Texas.