The Great Unknown of the Rio Grande

By Louis F. Aulbach. This is a guide for canoeing, kayaking or rafting the section of the Rio Grande in Big Bend National Park beginning at Terlingua Creek, the exit point for Santa Elena Canyon, including Boquillas Canyon and Mariscal Canyon, and ending at the bridge at La Linda, the starting point for trips through the Lower Canyons. Wilderness Area Map Service. 7 1/2" x 10&quot. 102 pages. 2007.