From San Antonio, Texas, it is 660 kilometers (410 miles) to the park headquarters at Panther Junction via U.S. 90 to Marathon and south on U.S. 385. Driving from the Persimmon Gap park entrance to park headquarters will consume 46 of these kilometers (29 miles). The gap is a low mountain pass once traversed by the Comanche War Trail, a thoroughfare northward for thousands of horses stolen in Mexico. Had you crossed this pass in 1859 you might have witnessed the U.S. military experimenting with camels as beasts of burden for this dry country. The cantankerous camels bettered the standard military mule on several points. However, the Civil War ended the camel tryouts. The camel’s aptness illustrates that you are traveling desert country. This calls for unique precautions, so please read the “Tips for Desert Travelers” on page 124. From El Paso it is 520 kilometers (323 miles) to Panther Junction via Interstate 10 to Van Horn, U.S. 90 to Alpine, and south via Texas 118. You enter the park at the Maverick entrance. Just west of the park here on Texas Ranch Road 170 is the ghost town of Terlingua, a worthwhile side trip. In the park’s western section you find the Painted Desert, eroded badlands formations showing distinct bands of colorful deposits from up to 70 million years ago. From El Paso and points west you can take U.S. 67 south from Marfa to Presidio, approaching the park on Texas Ranch Road 170, the Camino del Rio, at the Maverick entrance. From this entrance to the headquarters at Panther Junction is about 43 kilometers (27 miles). Water and gasoline are available in and around the park only at a few, and often widely separated, points. Check your water supply and gas gauge before you leave U.S. 90. Driving the Park. At Panther Junction you can purchase the _Road Guide to Paved and Improved Dirt Roads of Big Bend National Park_. It describes five tours and the points of interest en route. The Santa Elena and Basin drives begin at junctions along the park road from Maverick to Panther Junction. The Boquillas drive begins at Panther Junction. The Persimmon Gap and Maverick drives extend from their respective entrances to Panther Junction. A park map and information folder includes a large map showing major natural and historical features, roads, and facilities and services. It is available at Panther Junction in the administration building, and in dispensers at Persimmon Gap and Maverick. (Supplies at Maverick are sometimes exhausted.) Obtain a copy of this folder before your trip by calling or writing the Superintendent, Big Bend National Park, Texas 79834, (915) 477-2251. Primitive Roads.