What came to be known as the Fort Smith-Santa Fe Trail was first blazed in 1840 by trader Josiah Gregg, who sought a route to Santa Fe along the south side of the Canadian River. In 1849, Gregg's route was closely followed by a military escort led by Capt. Randolph B. Marcy, which traveled from Fort Smith, Arkansas, to Santa Fe with about 500 pioneers heading for California. The party entered Oldham County on June 13th and on June 14th ascended to the Llano Estacado near this site, where Marcy found the plains "as boundless...and trackless as the ocean...a desolate waste of uninhabited solitude." Eighty-five days after leaving Fort Smith, the party reached Santa Fe. After passing the plains, Marcy said he had never passed a country where wagons could move with as much ease and facility, without any labor in making a road, as upon this route. He advocated the trail as a prospective route for a transcontinental railroad, which was built after the Civil War, and later U.S. Highway 66 and Interstate 40 were laid close to the trail as the country entered the automobile age and developed the interstate highway system.