For the Texas State Park see Big Bend Ranch State Park.
Big Bend Ranch State Park is a 311,000-acre (126,000 ha) state park located on the Rio Grande in Brewster and Presidio counties, Texas. It is the largest state park in Texas. The closest major town is Presidio, Texas, where the state park's head office is located.
|Location||Chihuahuan Desert, Texas, United States|
|Area||801,163 acres (3,242.19 km2)|
|Established||June 12, 1944|
|Operator||National Park Service|
|Website|| Official website |
Big Bend National Park is an American national park located in West Texas, bordering Mexico. The park has national significance as the largest protected area of Chihuahuan Desert topography and ecology in the United States. The park protects more than 1,200 species of plants, more than 450 species of birds, 56 species of reptiles, and 75 species of mammals.
A national park is a park in use for conservation purposes. Often it is a reserve of natural, semi-natural, or developed land that a sovereign state declares or owns. Although individual nations designate their own national parks differently, there is a common idea: the conservation of 'wild nature' for posterity and as a symbol of national pride. An international organization, the International Union for Conservation of Nature (IUCN), and its World Commission on Protected Areas (WCPA), has defined "National Park" as its Category II type of protected areas.
West Texas is a loosely defined part of the U.S. state of Texas, generally encompassing the arid and semiarid lands west of a line drawn between the cities of Wichita Falls, Abilene, and Del Rio.
The Chihuahuan Desert is a desert and ecoregion designation covering parts of northern Mexico and the southwestern United States. It occupies much of West Texas, parts of the middle and lower Rio Grande Valley and the lower Pecos Valley in New Mexico, and a portion of southeastern Arizona, as well as the central and northern portions of the Mexican Plateau. It is bordered on the west by the extensive Sierra Madre Occidental range, along with northwestern lowlands of the Sierra Madre Oriental range. On the Mexican side, it covers a large portion of the state of Chihuahua, along with portions of Coahuila, north-eastern Durango, the extreme northern part of Zacatecas, and small western portions of Nuevo León. With an area of about 362,000 km2 (139,769 sq mi), it is the third largest desert of the Western Hemisphere and the second largest in North America, after the Great Basin Desert.
Geological features in the park include sea fossils and dinosaur bones, as well as volcanic dikes. The area has a rich cultural history, from archeological sites dating back nearly 10,000 years to more recent pioneers, ranchers, and miners.
A fossil is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood, oil, coal, and DNA remnants. The totality of fossils is known as the fossil record.
A dike or dyke, in geological usage, is a sheet of rock that is formed in a fracture in a pre-existing rock body. Dikes can be either magmatic or sedimentary in origin. Magmatic dikes form when magma flows into a crack then solidifies as a sheet intrusion, either cutting across layers of rock or through a contiguous mass of rock. Clastic dikes are formed when sediment fills a pre-existing crack.
In the history of art, prehistoric art is all art produced in preliterate, prehistorical cultures beginning somewhere in very late geological history, and generally continuing until that culture either develops writing or other methods of record-keeping, or makes significant contact with another culture that has, and that makes some record of major historical events. At this point ancient art begins, for the older literate cultures. The end-date for what is covered by the term thus varies greatly between different parts of the world.
The park encompasses an area of 801,163 acres (1,251.8 sq mi; 3,242.2 km2). For more than 1,000 miles (1,600 km), the Rio Grande/Río Bravo forms the boundary between Mexico and the United States, and Big Bend National Park administers approximately 118 miles (190 km) along that boundary. The park was named after a large bend in the river, and the Texas—Mexico border.
The Rio Grande is one of the principal rivers in the southwest United States and northern Mexico. The Rio Grande begins in south-central Colorado in the United States and flows to the Gulf of Mexico. Along the way, it forms part of the Mexico–United States border. According to the International Boundary and Water Commission, its total length was 1,896 miles (3,051 km) in the late 1980s, though course shifts occasionally result in length changes. Depending on how it is measured, the Rio Grande is either the fourth- or fifth-longest river system in North America.
Because the Rio Grande serves as an international boundary, the park faces unusual constraints while administering and enforcing park rules, regulations, and policies. In accordance with the Treaty of Guadalupe Hidalgo, the park's territory extends only to the center of the deepest river channel as the river flowed in 1848. The rest of the land south of that channel, and the river, lies within Mexican territory. The park is bordered by the protected areas of Parque Nacional Cañon de Santa Elena and Maderas del Carmen in Mexico.
The Treaty of Guadalupe Hidalgo, officially titled the Treaty of Peace, Friendship, Limits and Settlement between the United States of America and the Mexican Republic, is the peace treaty signed on February 2, 1848, in the Villa de Guadalupe Hidalgo between the United States and Mexico that ended the Mexican–American War (1846–1848). The treaty came into force on July 4, 1848.
The Protected Area of Flora and Fauna Santa Elena Canyon is a protected area for plants and wildlife in the Mexican municipalities of Manuel Benavides and Ojinaga, in the state of Chihuahua. It was founded on November 7, 1994 and has an area of 277,209 hectares.
Maderas del Carmen is a biosphere reserve in the northern Mexican state of Coahuila.
The park exhibits dramatic contrasts and its climate may be characterized as one of extremes. Dry and hot late spring and summer days often exceed 100 °F (38 °C) in the lower elevations. Winters are normally mild but subfreezing temperatures occasionally occur. Because of the range in altitude from about 1,800 feet (550 m) along the river to Emory Peak in the Chisos Mountains at 7,832 feet (2,387 m), a wide variation in available moisture and temperature exists throughout the park. These variations contribute to an exceptional diversity in plant and animal habitats. Some species in the park, such as the Chisos oak ( Quercus graciliformis ), are found nowhere else in the United States.
Emory Peak, located in Big Bend National Park, is the highest peak in the Chisos Mountains. and the highest in Brewster County. The peak is named for William H. Emory, the chief surveyor of the U.S. Boundary Survey team of 1852. From the Chisos Basin the peak appears to be a minor ridge, while the summit of Casa Grande, one mile closer, seems to be much taller. From the west, Emory Peak is clearly visible as a point slightly higher than most of the mountain range.
The Chisos Mountains are a mountain range located in the Big Bend area of West Texas, United States. The mountain range is contained entirely within the boundaries of Big Bend National Park. This is the only mountain range in the United States to be fully contained within the boundary of a national park. It is also the southernmost mountain range in the mainland United States.
Quercus graciliformis is a rare North American species of oak tree in the beech family.
The 118 mi (190 km) of river that form the southern park boundary include the spectacular canyons of Santa Elena, Mariscal, and Boquillas. The Rio Grande, which meanders through this portion of the Chihuahuan Desert, has cut deep canyons with nearly vertical walls through three uplifts made primarily of limestone. Throughout the open desert areas, the highly productive Rio Grande riparian zone includes numerous plant and animal species and significant cultural resources. The vegetative belt extends into the desert along creeks and arroyos.
South of the border lie the Mexican states of Chihuahua and Coahuila and newly protected areas for flora and fauna, which are regions known as the Maderas del Carmen and the Cañón de Santa Elena.
|Climate data for Castolon weather station, Texas. (Elevation 2,170ft)|
|Record high °F (°C)||90|
|Average high °F (°C)||68.2|
|Average low °F (°C)||34.5|
|Record low °F (°C)||7|
|Average precipitation inches (mm)||0.37|
|Source: The Western Regional Climate Center|
|Climate data for Chisos Basin weather station, Texas. (Elevation 5,300ft)|
|Record high °F (°C)||82|
|Average high °F (°C)||58.3|
|Average low °F (°C)||36.9|
|Record low °F (°C)||−3|
|Average precipitation inches (mm)||0.68|
|Source: The Western Regional Climate Center|
The oldest recorded tectonic activity in the park is related to the Paleozoic Marathon orogeny, although Proterozoic events (over 550 Mya) possibly have some deep control. The Marathon orogeny (part of the Ouachita-Marathon-Sonora orogenic belt) is part of thrusting of rocks from the South American Plate over the North American Plate. This can be best seen in the Persimmon Gap area of the park. This orogenic event is linked to the lack of Triassic- and Jurassic-age rocks in the park.
Between the Triassic and the Cretaceous, the South American Plate rifted from the North American Plate, resulting in the deposition of the Glen Rose Limestone, Del Carmen Limestone, Sue Peaks Formation, Santa Elena Limestone, Del Rio Clay, Buda Limestone, and Boquillas formations (preserved in the Sierra del Carmen–Santiago Mountains, Nine Point Mesa, Mariscal Mountain, and Mesa de Anguila areas). Also during this time, the Chihuahua trough formed as the Gulf of Mexico opened, which resulted in east-west striking normal faulting.As a result of this depositional time, dinosaur, forest and other fossils are preserved in the park.
Following the ending of rifting in the Late Cretaceous to the early Cenozoic, the Big Bend area was subjected to the Laramide orogeny. This period of (now east-west) compression caused the northeast-facing Mesa de Anguila (an uplifted monocline on the park's southwest margin), the southwest-facing Sierra del Carmen–Santiago Mountains (an uplifted and thrust-faulted monocline that forms the park's boundary on the east) and the Tornillo Basin. During the middle Cenozoic, most of the volcanic rocks, including the Chisos group, the Pine Canyon caldera complex, and the Burro Mesa Formation, formed.
The most recent tectonic activity in the park is basin and range faulting from the Neogene to Quaternary. This period of east-west extension has resulted in Estufa and Dehalo bolsons in the Chisos Mountains, as well as the Terlingua and Sierra del Carmen, Chalk Draw, and Burro Mesa faults. The Rio Grande has entered the Big Bend area roughly 2 million years ago, and since then, extensive erosion and downcutting have occurred.
Cultural resources in the park range from the Paleo-Indian period 10,500 years ago through the historic period represented by Native American groups, such as the Chisos, Mescaleros, and Comanche. More recently, Spanish, Mexican, Anglo, and Irish settlers farmed, ranched, and mined in the area.
Throughout the prehistoric period, humans found shelter and maintained open campsites throughout the park. The archeological record reveals an Archaic-period desert culture, whose inhabitants developed a nomadic hunting and gathering lifestyle that remained virtually unchanged for several thousand years.
The historic cultural landscape centers upon various subsistence or commercial land uses. The riparian and tributary environments were used for subsistence and irrigation farming. Transportation networks, irrigation structures, simple domestic residences and outbuildings, and planed and terraced farm land lining the stream banks characterize these landscapes.
During the early historic period (before 1535) several Indian groups were recorded as inhabiting the Big Bend. The Chisos Indians were a loosely organized group of nomadic hunters and gatherers who probably practiced limited agriculture on a seasonal basis. The origin of the Chisos Indians is not known. Linguistically, they were associated with the Conchos Indians of northern Chihuahua and northwestern Coahuila. Their language group spoke a variation of Uto-Aztecan, a language whose speakers ranged from central Mexico to the Great Basin of the U.S.
The Jumano was a nomadic group that traveled and traded throughout West Texas and southeastern New Mexico, but some historic records indicate they were enemies of the Chisos. Around the beginning of the 18th century, the Mescalero Apaches began to invade the Big Bend region and displaced the Chisos Indians. One of the last Native American groups to use the Big Bend was the Comanches, who passed through the park along the Comanche Trail on their way to and from periodic raids into the Mexican interior. These raids continued until the mid-19th century. The last of the great military leaders of the native peoples of the region was an Apache of Spanish ancestry named Alzate, who was active as late as the late 1860s.
The European presence in the region begins circa 1535 AD with the first Spanish explorations into this portion of North America. The expedition of Álvar Núñez Cabeza de Vaca passed near the Big Bend and was followed by other expeditions. Some of these expeditions were searching for gold and silver, or farm and ranch land. Others, such as those by the Franciscan missionaries, were intended to establish centers in which the natives could be evangelized. In an attempt to protect the northern frontier of the New Spain, from which emerged present-day Mexico, a line of presidios, or forts, was established along the Rio Grande in the late 18th century. The Presidio de San Vicente was built near present-day San Vicente, Coahuila, and the Presidio de San Carlos was built near present-day Manuel Benavides, Chihuahua. Some of the presidios were soon abandoned, because of financial difficulties and because they could not effectively stop Indian intrusions into Mexico. The soldiers and settlers of these presidios moved to newer presidios where the interests of the Spanish Empire were more defensible. Such was the case of Santa Rosa Maria del Sacramento, now Muzquiz, Coahuila.
Very little study has been made of the Spanish occupation of the Big Bend following the abandonment of the presidios. In 1805, a Spanish settlement called Altares existed 30 mi (48 km) south of the Rio Grande. The region became a part of Mexico when it achieved its independence from Spain in 1821. Mexican families lived in the area when English-speaking settlers began arriving following the secession of Texas during the latter half of the 19th century.
Following the end of the Mexican–American War in 1848, the U.S. Army made military surveys of the uncharted land of the Big Bend. Forts and outposts were established across Trans-Pecos Texas to protect migrating settlers from Indian attacks. A significant proportion of the soldiers in the late 1800s were African American and came to be called the "buffalo soldiers", a name apparently given to them by the Native Americans. Lieutenant Henry Flipper, the first American of African ancestry to graduate from West Point, served in Shafter, Texas, near the end of the 19th century. (Shafter, named for General William R. Shafter, lies west of the Big Bend along the highway from Presidio to Marfa.) Ranchers began to settle in the Big Bend about 1880, and by 1900, sheep, goat, and cattle ranches occupied most of the area. The delicate desert environment was soon overgrazed.
In the late 19th and early 20th century, valuable mineral deposits were discovered and brought settlers who worked in the mines or supported the mines by farming or by cutting timber for the mines and smelters. Communities sprang up around the mines. Boquillas and Terlingua both resulted from mining operations. During this period, the Rio Grande flood plain was settled by farmers. Settlements developed with names like Terlingua Abajo, San Vicente, La Coyota, and Castolon. Often, no more than clusters of families were living and farming in the same area, and they were successful only to the degree that the land was able to support them.
In the 1930s, many people who loved the Big Bend country saw that it was a land of unique contrast and beauty that was worth preserving for future generations. In 1933, the Texas Legislature passed legislation to establish Texas Canyons State Park. Later that year, the park was redesignated Big Bend State Park. In 1935, the United States Congress passed legislation that would enable the acquisition of the land for a national park. The State of Texas deeded the land that it had acquired to the federal government, and on June 12, 1944, Big Bend National Park became a reality. The park opened to visitors on July 1, 1944.
Despite its harsh desert environment, Big Bend has more than 1,200 species of plants (including 60 cactus species), over 600 species of vertebrates, and about 3,600 insect species. The variety of life is largely due to the diverse ecology and changes in elevation between the dry, hot desert, the cool mountains, and the fertile river valley.
Most of the animals are not visible in the day, particularly in the desert. The park comes alive at night, with many of the animals foraging for food. About 150 cougar (Puma concolor) sightings are reported per year, despite the fact that only two dozen cougars live in the park.Other species that inhabit the park include coyote (Canis latrans), kangaroo rat (Dipodomys spp.), greater roadrunner (Geococcyx californianus), golden eagle (Aquila chrysaetos), gray fox (Urycon cinereoargenteus), collared peccary (Pecari tajacu), and black-tailed jackrabbit (Lepus californicus). Mexican black bears (Ursus americanus eremicus) are also present in the mountain areas.
The variety of cactus and other plant life add color to the Big Bend region. Cactus species in the park include prickly pear ( Opuntia spp.), claretcup ( Echinocereus coccineus ), and pitaya ( E. enneacanthus ). In the spring, the wildflowers are in full bloom and the yucca flowers display bright colors. Bluebonnets (Lupinus spp.) are prevalent in Big Bend, and white and pink bluebonnets are sometimes visible by the road. Other flowering plants such as the desert marigold ( Baileya multiradiata ), desert willow ( Chilopsis linearis ), ocotillo ( Fouquieria splendens ), rock nettle ( Eucnide urens ), and lechuguilla ( Agave lechuguilla ) abound in Big Bend.
The first U.S. record of the northern tufted flycatcher (Mitrephanes phaeocercus), a Central American species, was from this site in November 1991. Birders also flock to the park, as it is home to the only area in the United States within the breeding range of the Colima warbler (Vermivora crissalis).
Plans to reintroduce the Mexican wolf to Big Bend National Park were rejected in the late 1980s by the state of Texas. Disagreement over the reintroduction included the question of whether the park contained enough prey animals, such as deer and javelinas, to sustain a wolf population.
Big Bend is one of the largest, most remote, and one of the least-visited national parks in the contiguous United States. In the 10 year period from 2007 to 2016, an average of about 352,000 visitors entered the park annually.
Big Bend's primary attraction is its hiking and backpacking trails. Particularly notable among these are the Chimneys Trail, which visits a rock formation in the desert; the Marufo Vega trail, a loop trail that passes through scenic canyons on the way to and from the Rio Grande; the South Rim trail which circles the high mountains of the Chisos; and the Outer Mountain Loop trail in the Chisos, which incorporates parts of the South Rim loop, descends into the desert along the Dodson Trail, and then returns to the Chisos Basin, completing a 30-mile loop. Other notable locations include Santa Elena Canyon, Grapevine Hills, and the Mule Ears, two imposing rock towers in the middle of the desert. Professional backpacking guide services provide trips in the park.
The park administers 118 miles (190 km) of the Rio Grande for recreational use. Professional river outfitters provide tours of the river. Use of a personal boat is permitted, but a free river float permit is required. In June 2009, the Department of Homeland Security began treating all float trips as trips that had left the country and required participants to have an acceptable form of identification such as a passport to re-enter the country.
Visitors often cross the Rio Grande to visit the Mexican village of Boquillas. The Department of Homeland Security closed the border crossing in 2002 due to increased security following the September 11 attacks, but in April 2013, the Boquillas crossing reopened as an official Class B Port of Entry between the U.S. and Mexico. It is open Wednesday through Sunday between 9 am and 6 pm.
With more than 450 species of birds recorded in the park, a widely popular activity is birdwatching. Many species stop in the park during their annual migrations.
Five paved roads are in Big Bend. Persimmon Gap to Panther Junction is a 28-mile (45 km) road from the north entrance of the park to park headquarters at Panther Junction. Panther Junction to Rio Grande Village is a 21-mile (34 km) road that descends 2,000 feet (610 m) from the park headquarters to the Rio Grande. Maverick Entrance Station to Panther Junction is a 23-mile (37 km) route from the western entrance of the park to the park headquarters. Chisos Basin Road is 6 miles (10 km) long and climbs to 5,679 feet (1,731 m) above sea level at Panther Pass before descending into the Chisos Basin. The 30-mile (48 km) Ross Maxwell Scenic Drive leads to the Castolon Historic District and Santa Elena Canyon.
In 2012, the park was designated an international dark-sky park by the International Dark-Sky Association. The association also recognized the park with its Gold Tier designation as "free from all but the most minor impacts of light pollution." Measurements made by the National Park Service show that Big Bend has the darkest skies in the contiguous United States.Thousands of stars, bright planets, and the Milky Way are visible on clear nights.
Brewster County is a county located in the western part of the U.S. state of Texas. As of the 2010 census, the population was 9,232. Its county seat and only city is Alpine. The county is named for Colonel Henry Percy Brewster, a Secretary of War for the Republic of Texas.
The Big Bend is a colloquial name of a geographic region in the western part of the state of Texas in the United States along the border with Mexico, roughly defined as the counties north of the prominent northward bend in the Rio Grande as it passes through the gap between the Chisos Mountains in Texas and the Sierra Madre Oriental in Mexico. It is sometimes loosely defined as the part of Texas south of U.S. Highway 90 and west of the Pecos River. The region includes three counties in Texas: Brewster, Jeff Davis and Presidio.
Boquillas del Carmen, frequently known simply as Boquillas, is a village in northern Mexico on the banks of the Rio Grande. It is the northernmost populated place in the municipality of Ocampo, which lies within the Mexican state of Coahuila. Situated next to the Mexico–United States border, visitors on foot from the United States can enter the village via the Boquillas Port of Entry and tourism is the principal industry in Boquillas.
Mescalero or Mescalero Apache is an Apache tribe of Southern Athabaskan Native Americans. The tribe is federally recognized as the Mescalero Apache Tribe of the Mescalero Apache Reservation, located in south central New Mexico.
Terlingua is a mining district and census-designated place (CDP) in southwestern Brewster County, Texas, United States. It is located near the Rio Grande and the villages of Lajitas and Study Butte, Texas, as well as the Mexican state of Chihuahua. The discovery of cinnabar, from which the metal mercury is extracted, in the mid-1880s brought miners to the area, creating a city of 2,000 people. The only remnants of the mining days are a ghost town of the Howard Perry-owned Chisos Mining Company and several nearby capped and abandoned mines, most notably the California Hill, the Rainbow, the 248, and the Study Butte mines. The mineral terlinguaite was first found in the vicinity of California Hill.
The Trans-Pecos, as originally defined in 1887 by the Texas geologist Robert T. Hill, is the portion of Texas that lies west of the Pecos River. The term is considered synonymous with "Far West Texas", a subdivision of West Texas. The Trans-Pecos is part of the Chihuahuan Desert, the largest desert in North America. It is the most mountainous and arid portion of the state, and most of its area is vast and sparsely populated, comprising seven of the ten largest counties by area in Texas. The area is known for the natural environment of the Big Bend and the gorge of the Rio Grande, part of which has been designated a National Wild and Scenic Rivers System. With the notable exceptions of Big Bend Ranch State Park, Big Bend National Park and the Guadalupe Mountains National Park, the vast majority of the Trans-Pecos region consists of privately owned ranchland. However, the majority of the region's population reside in the El Paso metropolitan area.
The Rio Grande Wild and Scenic River is a U.S. National Wild and Scenic River that protects 260 miles (420 km) of the Rio Grande in New Mexico and Texas. The designation was first applied in 1968 to a 55.7-mile (89.6 km) stretch of the river in New Mexico; an additional 191.2 miles (307.7 km) of the river in Texas was added in 1978, followed by another 12.5 miles (20.1 km) in New Mexico in 1994.
The geography of Texas is diverse and large. Occupying about 7% of the total water and land area of the U.S., it is the second largest state after Alaska, and is the southernmost part of the Great Plains, which end in the south against the folded Sierra Madre Oriental of Mexico. Texas is in the south-central part of the United States of America, and is considered to form part of the U.S. South and also part of the U.S. Southwest.
State Highway 118, or SH 118, is a 155.3-mile (249.9 km) state highway in the U.S. state of Texas that runs from Big Bend National Park north to Kent and passes through the towns of Study Butte, Alpine, and Fort Davis. SH 118 is maintained by the Texas Department of Transportation (TxDOT). The road lies entirely within the Trans-Pecos region of Texas. SH 118 is a two-lane road along its length except for a section in Alpine where the route follows the path of U.S. Route 67 and U.S. Route 90. All of the route except for the 2.8-mile (4.5 km) section between Big Bend National Park and Farm to Market Road 170 is included in the Texas Historical Commission's Texas Mountain Trail.
Boquillas was a small settlement in Texas, located on the northern banks of the Rio Grande. It was located within Brewster County, 5 miles northeast of San Vicente, Texas. The place existed to service the mining operations at Boquillas del Carmen, Mexico, just across the Rio Grande.
Farm to Market Road 170, Farm Road 170, or FM 170 is a 114.6-mile (184.4 km) highway maintained by the Texas Department of Transportation (TxDOT) in Presidio and Brewster counties in Texas. The route, known locally as the River Road, runs along the United States side of the Rio Grande which in Texas forms the international boundary between the U.S. and Mexico. The road runs from Candelaria through the city of Presidio as well as several smaller communities and former settlements to State Highway 118 in Study Butte near Big Bend National Park. The road also passes through the southern portion of Big Bend Ranch State Park.
Lajitas is an unincorporated community in Brewster County, Texas, United States, near the Big Bend National Park.
Castolon, also known as La Harmonia Ranch and Campo Santa Helena, was a small community in southwestern Texas, located in what is now Big Bend National Park along the Rio Grande. The location was first settled in 1901 by Cipriano Hernandez, who farmed the area and built the original Castolon Store, now known as the Alvino House.
The Comanche Trail, sometimes called the Comanche War Trail or the Comanche Trace, was a travel route in Texas established by the nomadic Comanche nation. The route ran from the Comanche summer hunting grounds to the Rio Grande, where the Spanish had established a line of missions and presidios during the eighteenth century in what was then called New Spain, which the Comanche would raid. Although called a "trail," the Comanche Trail was actually a network of parallel and branching trails, always following sources of good water. By 1857 parts of the trail had been named and appeared on maps.
The Sierra del Carmen, also called the Sierra Maderas del Carmen, is a northern finger of the Sierra Madre Oriental in the state of Coahuila, Mexico. The Sierra begins at the Rio Grande at Big Bend National Park and extends southeast for about 45 miles (72 km), reaching a maximum elevation of 8,920 feet (2,720 m). Part of the Sierra del Carmen is protected in the Maderas del Carmen Biosphere Reserve as part of a bi-national effort to conserve a large portion of the Chihuahua Desert in Mexico and Texas.