ARState of ArkansasArkansan
The highlands are part of the Southern Interior Highlands, including The Ozarks and the Ouachita Mountains. The southern lowlands include the Gulf Coastal Plain and the Arkansas Delta. This dual split can yield to general regions named northwest, southwest, northeast, southeast, or central Arkansas. These directionally named regions are broad and not defined along county lines. Arkansas has seven distinct natural regions: the Ozark Mountains, Ouachita Mountains, Arkansas River Valley, Gulf Coastal Plain, Crowley's Ridge, and the Arkansas Delta, with Central Arkansas sometimes included as a blend of multiple regions.


Ozark MountainsOzarkthe Ozarks
To the south, the Arkansas River valley separates the Boston Mountains from the Ouachita Mountains. Missouri Ozark rivers include the Gasconade, Big Piney, and Niangua rivers in the north central region. The Meramec River and its tributaries Huzzah Creek and Courtois Creek are found in the northeastern Ozarks. The Black and St. Francis rivers mark the eastern crescent of the Ozarks. The James, Spring and North Fork rivers are in south-central Missouri. Forming the west central border of the Ozarks from Missouri through Kansas and into Oklahoma are the Spring River and its tributary, Center Creek.

Appalachian Mountains

AppalachiansAppalachianAppalachian Mountain
The Ouachita Mountains in Arkansas and Oklahoma were originally part of the Appalachians as well but became disconnected through geologic history. While exploring inland along the northern coast of Florida in 1528, the members of the Narváez expedition, including Álvar Núñez Cabeza de Vaca, found a Native American village near present-day Tallahassee, Florida whose name they transcribed as Apalchen or Apalachen. The name was soon altered by the Spanish to Apalachee and used as a name for the tribe and region spreading well inland to the north. Pánfilo de Narváez's expedition first entered Apalachee territory on June 15, 1528, and applied the name.

Ouachita National Forest

Arkansas National ForestOuachitaOuatchita
The Ouachita National Forest is a National Forest that lies in the western portion of Arkansas and portions of eastern Oklahoma. The Ouachita National Forest is the oldest National Forest in the southern United States. The forest encompasses 1784457 acre, including most of the scenic Ouachita Mountains. Six locations in the forest, comprising 65000 acre, have been designated as wilderness areas. Ouachita is the French spelling of the Indian word Washita, which means "good hunting grounds." The forest was known as Arkansas National Forest on its establishment on December 18, 1907; the name was changed to Ouachita National Forest on April 29, 1926.

U.S. Interior Highlands

Interior Highlands105 Interior Highlandsa highland region
The Ouachita Mountains of Arkansas and Oklahoma, which can be divided into a number of subranges including the mountains of the Arkansas River Valley (called the Frontal Ouachita Mountains); the highest point is Mount Magazine at 2753 ft. The Boston Mountains of the Arkansas and Oklahoma Ozark Plateaus; the highest point is Buffalo Lookout at 2561 ft. The St. Francois Mountains of the Missouri Ozark Plateaus; the highest point is Taum Sauk Mountain at 1772 ft.


TXTexanState of Texas
This is the buried crest of the Appalachian Mountains–Ouachita Mountains zone of Pennsylvanian continental collision. This orogenic crest is today buried beneath the Dallas–Waco—Austin–San Antonio trend. The late Paleozoic mountains collapsed as rifting in the Jurassic period began to open the Gulf of Mexico. Pangea began to break up in the Triassic, but seafloor spreading to form the Gulf of Mexico occurred only in the mid and late Jurassic. The shoreline shifted again to the eastern margin of the state and the Gulf of Mexico passive margin began to form.


Choctaw IndiansChoctawsChoctaw people
Choctaw Nation of Oklahoma (official site). Jena Band of Choctaw Indians (official site). Choctaw Store. Choctaw Indian Fair. "Choctaws" by Dr. D.L. Birchfield. Choctaw, Oklahoma Historical Society article.

Southern United States

SouthSouthernAmerican South
The other divisions, West South Central (Texas, Oklahoma, Arkansas, and Louisiana) and South Atlantic (West Virginia, Delaware, Maryland, Virginia, North Carolina, South Carolina, Georgia, and Florida) ranked seventh and fifth, respectively. The South had a significantly higher rate of hospital discharges in 2005 than other regions of the United States, but the rate had declined to be closer to the overall national rate by 2011.


coyotesCanis latranseastern coyote
The coyote (Canis latrans) is a canine native to North America. It is smaller than its close relative, the gray wolf, and slightly smaller than the closely related eastern wolf and red wolf. It fills much of the same ecological niche as the golden jackal does in Eurasia, though it is larger and more predatory, and is sometimes called the American jackal by zoologists. Other names for the species, largely historical, include prairie wolf and brush wolf.

Juniperus virginiana

red cedareastern red cedarcedar
In the Missouri, Oklahoma and Arkansas Ozarks, eastern juniper is commonly used as a Christmas tree. The pollen is a known allergen, although not as potent as that of the related Juniperus ashei (Ashe juniper), which sheds pollen a month earlier. People allergic to one are usually allergic to both. J. virginiana sheds pollen as early as late winter and through early spring. Consequently, what begins as an allergy to Ashe juniper in the winter may extend into spring, since the pollination of the eastern juniper follows that of the Ashe juniper. Contact with the leaves or wood can produce a mild skin rash in some individuals.

United States

In 2018, Oklahoma had the highest incarceration rate (1,079 per 100,000 people), and Massachusetts the lowest (324 per 100,000 people). Among the U.S. territories, the highest incarceration rate was in the U.S. Virgin Islands (542 per 100,000 people) and the lowest was in Puerto Rico (313 per 100,000 people). According to the International Monetary Fund, the U.S. GDP of $16.8 trillion constitutes 24% of the gross world product at market exchange rates and over 19% of the gross world product at purchasing power parity (PPP). The nominal GDP of the U.S. is estimated to be $17.528 trillion.

White-tailed deer

deerwhitetail deerOdocoileus virginianus
., the species is the state animal of Arkansas, Illinois, Michigan, Mississippi, Nebraska, New Hampshire, Ohio, Pennsylvania, and South Carolina, the wildlife symbol of Wisconsin, and game animal of Oklahoma. The profile of a white-tailed deer buck caps the coat of arms of Vermont and can be seen in the flag of Vermont and in stained glass at the Vermont State House. It is the national animal of Honduras and Costa Rica and the provincial animal of Canadian Saskatchewan and Finnish Pirkanmaa. Texas is home to the most white-tailed deer of any U.S. state or Canadian province, with an estimated population of over four million.

Louisiana Purchase

LouisianaLouisiana TerritorySale of Louisiana
The purchase included land from fifteen present U.S. states and two Canadian provinces, including the entirety of Arkansas, Missouri, Iowa, Oklahoma, Kansas, and Nebraska; large portions of North Dakota and South Dakota; the area of Montana, Wyoming, and Colorado east of the Continental Divide; the portion of Minnesota west of the Mississippi River; the northeastern section of New Mexico; northern portions of Texas; New Orleans and the portions of the present state of Louisiana west of the Mississippi River; and small portions of land within the present Canadian provinces of Alberta and Saskatchewan.

Arkansas River Valley

Arkansas ValleyArkansasArkansas River Basin
Ouachita Mountains. The Ozarks.

Gulf of Mexico

GulfGulf CoastMexican Gulf
This land lay south of a continuous mountain range that extended from north-central Mexico, through the Marathon Uplift in West Texas and the Ouachita Mountains of Oklahoma, and to Alabama where it linked directly to the Appalachian Mountains. It was created by the collision of continental plates that formed Pangea. As interpreted by Roy Van Arsdale and Randel T. Cox, this mountain range was breached in Late Cretaceous times by the formation of the Mississippi Embayment. Geologists and other Earth scientists agree in general that the present Gulf of Mexico basin originated in Late Triassic time as the result of rifting within Pangea.

Arkansas River

ArkansasArkansas River ValleyArkansas (Napestle) River
These locks and dams allow the river to be navigable by barges and large river craft downriver of Muskogee, Oklahoma, where the McClellan-Kerr Arkansas River Navigation System joins in with the Verdigris River. Into western Arkansas, the river path works between the encroaching Boston and Ouachita Mountains, including many isolated, flat-topped mesas, buttes, or monadnocks such as Mount Nebo, Petit Jean Mountain, and Mount Magazine, the highest point in the state. The river valley then expands as it encounters much flatter land beginning just west of Little Rock, Arkansas. It continues eastward across the plains and forests of eastern Arkansas until it flows into the Mississippi River.

South Central United States

South Centralsouth-centralSouthern Plains
A large portion of the northeastern quarter of the region is mountainous, with the Ozark and Ouachita Mountains of Arkansas and eastern Oklahoma. The northwest quarter of the region is dominated by the Great Plains which become progressively drier west of 100° W, forming the North American Llano Estacado. The southwestern portions border the Rio Grande, and are generally drier than other areas of the South Central United States. Texas is the largest South Central state by both area and population. Texas is still home to over half the region's population. The largest city in the region, Houston, is located in Texas.

Arbuckle Mountains

The area is also the location of several campgrounds, including the YMCA's Camp Classen and the Baptist General Convention of Oklahoma's Falls Creek Baptist Conference Center, which hosts 55,000 campers each summer. James S. Aber, Arbuckle Mountains, Oklahoma. Robert W. Allen, 2002, Complex Structural Features of the Ardmore Basin. USGS America's Volcanic Past: Oklahoma. Kevin W. Blackwood, 2012, The Arbuckle Karst Conservancy. Arbuckle Mountains - Video footage of the area and a list of local activities and resources. Encyclopedia of Oklahoma History and Culture - Arbuckle Mountains. Oklahoma Digital Maps: Digital Collections of Oklahoma and Indian Territory.

Green Country

Northeastern OklahomaEastern OklahomaGreen Country (Oklahoma)
A small portion of the Ouachita Mountains extend into the southern areas of northeast Oklahoma, though the Ozark highlands are the primary range in the area. Northeast Oklahoma has a land area of 13247 sqmi, comprising eighteen entire counties. The region comprises about 19.3 percent of Oklahoma's land area, and is larger than the state of Maryland. Based on commuting patterns, the adjacent micropolitan area of Bartlesville, is grouped together in the (CSA). The population of this wider region is 998,438—more than one-fourth of Oklahoma's population—as of 2012.

Wichita Mountains

WichitaWichita OrogenyLonghorn Mountain
America's Volcanic Past - Oklahoma. Oklahoma Digital Maps: Digital Collections of Oklahoma and Indian Territory. O'Dell, Larry: Holy City of the Wichitas Pageant - Encyclopedia of Oklahoma History and Culture - Oklahoma Historical Society. Splinter, Dale K. and Marston, Richard A.: Wichita Mountains - Encyclopedia of Oklahoma History and Culture - Oklahoma Historical Society. O'Dell, Larry: Wichita Mountains National Wildlife Refuge - Encyclopedia of Oklahoma History and Culture - Oklahoma Historical Society.

McCurtain County, Oklahoma

McCurtainMcCurtain CountyGolden
McCurtain County's location in southeastern Oklahoma places it within a 10-county area designated for tourism purposes by the Oklahoma Department of Tourism and Recreation as Choctaw Country. According to the U.S. Census Bureau, the county has a total area of 1902 sqmi, of which 1850 sqmi is land and 52 sqmi (2.8%) is water. It is the third-largest county in Oklahoma by area. The terrain of McCurtain county varies from the foothills of the Ouachita Mountains in the northern part of the county to the rich Red River bottoms of the southern part. Sections of the Mountain Fork and Little River drainages lie in McCurtain county.

Atoka County, Oklahoma

AtokaAtoka County
The Ouachita Mountains are in the eastern part of the county, while the Sandstone Hills and Coastal Plains physiographic regions provide a more level terrain suitable for agriculture in the north and western part of the county. About 12 miles WSW of the town of Atoka is Boggy Depot State Park, the historic site of a once large community on the Butterfield Overland Mail stagecoach route. The Katian Age of the Ordovician Period of geological time is named for Katy Lake which is 2 miles north east of Atoka. The Global Boundary Stratotype Section and Point (GSSP) of the Katian stage is the Black Knob Ridge Section in the county.

Jackfork Sandstone

The Jackfork Sandstone, also referred to as the Jackfork Group, is a geologic formation associated with the Ouachita Fold and Thrust Belt exposed in western Arkansas and southeastern Oklahoma. It is named for Jackfork Mountain in Pittsburg and Pushmataha counties, Oklahoma. The Jackfork Sandstone is a thin- to massive-bedded, fine- to coarse-grained, brown, tan, or gray quartzitic sandstone with subordinate brown, silty sandstone and dark gray shale. It outcrops from Pulaski County, Arkansas in the east to Atoka County, Oklahoma in the west, a distance of over 200 miles.

Ouachita orogeny

OuachitaOuachita UpliftOuachita orogen
The collision of South American and Laurentian continental crust compressed and uplifted the region to form the Ouachita Mountains. During the Pennsylvanian and Permian, river systems draining westward from the Ouachita Mountains deposited sediments in north-central Texas and Oklahoma, which are now exposed at the surface. The Ouachita Mountains were extensively eroded between the Permian and the Jurassic, and much of the Ouachita system was subsequently buried beneath Mesozoic and Cenozoic sediments to the southeast and southwest. The structures there have only been revealed through deep drilling in petroleum exploration.

Collier Shale

The Collier Shale is a geologic formation in the Ouachita Mountains of Arkansas and Oklahoma. Dating from the Late Cambrian to Early Ordovician periods, the Collier Shale is the oldest stratigraphic unit exposed in Arkansas. First described in 1892, this unit was not named until 1909 by Albert Homer Purdue in his study of the Ouachita Mountains of Arkansas. Purdue assigned the type locality to the headwaters of Collier Creek in Montgomery County, Arkansas, but did not designate a stratotype. As of 2017, a reference section for this unit has yet to be designated. * Acanthodus. A. lineatus. Acodus. A. oneotensis. Chosonodina. C. herfurthi. Cordylodus. C. angulatus. Drepanodus. D. subarcuatus.