El Camino Real de Tierra Adentro, Spanish for “The Royal Road of the Interior”, represents a 1,600 mile-long trade route between Mexico City and Santa Fe. In use from 1598 to 1882, the route provided an established avenue for trade goods crossing the Mexican interior during a period of colonial rule spanning over two centuries. This artery of commerce and travel served at one time as the longest road in North America. It began as a system of informal Native American trails utilized by Spanish conquistadors and colonizers until the arrival of Juan de Onate’s expedition in 1598, the year the route achieved official status as the thoroughfare linking the provinces of the old Viceroyalty of New Spain. Sovereignties changed over the next three hundred years but the route remained, accommodating a growing and changing quantity of trade goods and cultures. Today, the route has been designated a National Historic Trail with over 400 miles bound by the U.S. borders under the stewardship of the National Parks Service. The route generally follows the Rio Grande River, entering Texas at the state’s farthest western point, encompassing the historic sites and pueblos of Mission Ysleta and Mission Socorro, and the communities of El Paso and San Elizario, before crossing the border and heading to Mexico City. Texas heritage travelers have the opportunity to explore the details and corresponding sites of interest at Keystone Heritage Park, the El Paso Museum of History, and the Chamizal National Monument.