Llano Estacado

According to Wikipedia, "The Llano Estacado commonly known as the Staked Plains...eccompasses parts of eastern New Mexico and northwestern Texas. One of the largest mesas or tablelands on the North American continent the elevation rises from 3,000 feet in the southeast to over 5,000 feet in the northwest, sloping almost uniformly at about 10 feet per mile." "It covers all or part of 33 Texas counties." "Interstate 40 crosses the northern portion from east of Amarillo to Tucumcari, New Mexico. Interstate 27 runs north-south between Amarillo and Lubbock, while Interstate 20 passes through the southern portion...west of Midland and Odessa." Image credit @txhistcomm