Oklahoma

===Topography===

{{See also|List of lakes in Oklahoma}}

Oklahoma is between the [[Great Plains]] and the [[Ozarks|Ozark Plateau]] in the [[Gulf of Mexico]] watershed,<ref name="Geography Map">{{cite web|date=April 17, 2003 |publisher=[[United States Geological Survey]] |access-date=July 31, 2007 |url=http://tapestry.usgs.gov/physiogr/physio.html |title=A Tapestry of Time and Terrain |archive-url=https://web.archive.org/web/20060515044037/http://tapestry.usgs.gov/physiogr/physio.html |archive-date=May 15, 2006 }}</ref> generally sloping from the high plains of its western boundary to the low wetlands of its southeastern boundary.<ref name="The Geography of Oklahoma">{{cite web | date=July 31, 2007 | publisher=Netstate | access-date=July 31, 2007 | url=http://www.netstate.com/states/geography/ok_geography.htm| title=The Geography of Oklahoma}}</ref><ref name="Topography of Oklahoma">{{cite web | year=2006 | publisher=geology.com | access-date=August 1, 2007 | url=http://geology.com/state-map/oklahoma.shtml | title=Oklahoma State Map Collection}}</ref> Its highest and lowest points follow this trend, with its highest peak, [[Black Mesa (Oklahoma)|Black Mesa]], at {{convert|4973|ft}} above sea level, situated near its far northwest corner in the [[Oklahoma Panhandle]]. The state's lowest point is on the Little River near its far southeastern boundary near the town of [[Idabel, Oklahoma|Idabel]], which dips to {{convert|289|ft}} above sea level.<ref name="The Climate of Oklahoma">{{cite web | date=January 1, 2003 | first=Derek |last=Arndt| publisher=Oklahoma Climatological Survey| access-date=July 31, 2007 | url=http://cig.mesonet.org/climateatlas/doc60.html | title=The Climate of Oklahoma}}</ref>

Among the most geographically diverse states, Oklahoma is one of four to harbor more than 10 distinct [[ecoregion|ecological regions]], with 11 in its borders—more per square mile than in any other state.<ref name="Oklahoma Terrain">{{cite web|date=January 12, 2006 |url=http://www.travelok.com/atv/index.asp |title=Oklahoma, All Terrain Vacation |website=TravelOK |publisher=TravelOK.com |access-date=July 15, 2006 |archive-url=https://web.archive.org/web/20060709205916/http://travelok.com/atv/index.asp |archive-date=July 9, 2006 }}</ref> Its western and eastern halves, however, are marked by extreme differences in geographical diversity: Eastern Oklahoma touches eight ecological regions and its western half contains three. Although having fewer ecological regions Western Oklahoma contains many rare, relic species.<ref name="Oklahoma Terrain"/>

Oklahoma has four primary mountain ranges: the [[Ouachita Mountains]], the [[Arbuckle Mountains]], the [[Wichita Mountains]], and the [[Ozarks|Ozark Mountains]].<ref name="The Geography of Oklahoma"/> Contained within the [[U.S. Interior Highlands]] region, the Ozark and Ouachita Mountains are the only major mountainous region between the [[Rocky Mountains]] and the [[Appalachian Mountains|Appalachians]].<ref>{{cite web | date=March 7, 2007 | url=http://www.srs.fs.usda.gov/4159/about/HotSpringsOffice.htm | title=Managing Upland Forests of the Midsouth | publisher=USD Forest Service| access-date=July 31, 2007|archive-url=https://web.archive.org/web/20080622180232/http://www.srs.fs.usda.gov/4159/about/HotSpringsOffice.htm|archive-date=June 22, 2008}}</ref> A portion of the [[Flint Hills]] stretches into north-central Oklahoma, and near the state's eastern border, The Oklahoma Tourism & Recreation Department regards [[Cavanal Hill]] as the world's tallest hill; at {{Convert|1999|ft|}}, it fails their definition of a mountain by one foot.<ref name="TravelOK">{{cite web | year=2007 | url=http://www.travelok.com/about/index.asp | title=About Oklahoma | publisher=TravelOK.com | access-date=July 10, 2006 | archive-url=https://web.archive.org/web/20060707070748/http://www.travelok.com/about/index.asp | archive-date=July 7, 2006 | df=mdy-all }}</ref>

The [[Semi-arid climate|semi-arid]] [[High Plains (United States)|high plains]] in the state's [[northwestern Oklahoma|northwestern corner]] harbor few natural forests; the region has a rolling to flat landscape with intermittent [[canyon]]s and [[mesa]] ranges like the [[Glass Mountains]]. Partial plains interrupted by small, [[sky island]] mountain ranges like the [[Antelope Hills, Oklahoma|Antelope Hills]] and the [[Wichita Mountains]] dot [[southwestern Oklahoma]]; transitional prairie and [[oak savanna]]s cover the [[Central Oklahoma|central portion]] of the state. The Ozark and Ouachita Mountains rise from west to east over the state's eastern third, gradually increasing in elevation in an eastward direction.<ref name="Topography of Oklahoma"/><ref name="forests 1"/>

More than 500 named creeks and rivers make up Oklahoma's waterways, and with 200 lakes created by dams, it holds the nation's highest number of artificial reservoirs.<ref name="TravelOK"/> Most of the state lies in two primary [[drainage basin]]s belonging to the [[Red River of the South|Red]] and [[Arkansas River|Arkansas]] Rivers, though the Lee and Little Rivers also contain significant drainage basins.<ref name="forests 1"/>
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File:turner falls ok.jpg|Turner Falls
File:Rose rocks.jpg|State rock ([[Desert rose (crystal)|rose rock]]) specimens from Cleveland County
File:Illinois River Oklahoma.jpg|alt=|Illinois River in northeastern Oklahoma
File:Elk Mountain, OK.jpg|Elk Mountain, in the eastern Wichita Mountains, southwestern Oklahoma
File:Wichita Mountains Narrows.jpg|Wichita Mountains Narrows
File:Talimenavista1.jpg|The [[Ouachita Mountains]] cover much of [[Kiamichi Country|southeastern Oklahoma]].
File:McIntosh County (Oklahoma).jpg|Grave Creek in [[McIntosh County, Oklahoma|McIntosh County]]
File:Gloss Mountains.jpg|[[Glass Mountains|Mesas]] rise above one of Oklahoma's state parks.
</gallery>