The Mountain Island
The Chisos Mountains are an isolate range rising to more than 7,000 feet from the desert basin. Entirely enclosed within Big Bend, this volcanic highland contains distinct forest zones, grading from pinyon-juniper-oak woodlands to higher-elevation conifer associations of ponderosa pine, quaking aspen, Arizona cypress and Douglas fir. The Chisos contain the only populations of drooping juniper, a beautiful species more widespread in Mexico, in the United States. Take the 4.8-mile (round-trip) Lost Mine Trail for a great introduction to Chisos Mountain ecology and scenery; the route climbs more than 1,000 feet and provides superb vistas. Ambitious hikers can summit Emory Peak---at 7,832 feet, the highest point in Big Bend---on a 9-mile round-trip trek leading off the Pinnacles Trail.
The Santa Elena
Hike or boat into Santa Elena Canyon, where the Rio Grande flows through a 1,500-foot deep gorge excavated from the great Mesa de Anguila. (According to the Park Service, some geologists suspect the three great canyons of Big Bend---the Santa Elena, Mariscal and Boquillas---were sculpted not by the Rio Grande but by the ancestral Rio Conchos, which today is a major tributary of the former stream entering it just upstream of the park.) Head northwest from the Castolon Visitor Center to take in the view from the Santa Elena Canyon Overlook, then drive to the trailhead for one of the more popular day hikes (1.7 miles round-trip) in the park. Rafters can float through the spectacular defile on guided or independent trips but are advised to check river conditions at the visitor centers when they pick up the required permit.
Cap a day of adventuring by taking in the sunset on the limestone battlement of the Sierra del Carmen, a striking range rising south of the Rio Grande in Mexico. Though the mountains aren't actually in Big Bend, the parade of shifting colors on their rugged face is a spectacle park visitors can enjoy from various spots, including the road between Panther Junction and Boquillas Canyon.
Enjoy the remarkably rich vegetation of Big Bend, which lies in the botanically diverse Chihuahuan Desert. More than 1,000 plant species are found in the park---more than 65 types of cactus alone. Among them are the century plant, a large agave that blooms only once in a lifetime that may span 30 or more years, and the flashy ocotillo, which sends up lofty, spined arms topped in the spring with red flowers.
Keep your eyes peeled for everything from peccaries to mountain lions while roaming Big Bend's roads and trails. The park's diversity of habitats results in impressive faunal diversity. Jackrabbits and hummingbirds inhabit the desert scrub, while the island forests of the Chisos Mountains support black bears and Montezuma quail.