In 1541, Francisco Vazquez de Coronado wrote to Charles I, King of Spain, describing for the first time the Llano Estacado or Staked Plains. The Llano is a high tableland extending across much of the Texas panhandle and eastern New Mexico. In Texas its eastern boundary is marked by the impressive Caprock which runs hundreds of miles across west Texas. Coronado was overwhelmed by the vastness of the Llano Estacado. As he wrote, “I reached plains so vast that I did not find their limit anywhere I went, although I travelled over them for 300 leagues.” He further describes them as having “no more land marks than if we had been swallowed up by the sea. There was not a stone, nor a bit of rising ground, nor a tree, nor a shrub, nor anything to go by.” He was also the first to write about the incredible herds of cattle (bison) that he encountered and the first to describe the various plains Indians that he encountered. Of course, he never found the Cities of Gold that he was looking for.