Entry Category: Geography - Starting with I

Flowing through the Ozark borderlands of eastern Oklahoma and western Arkansas, the Illinois River is fed by 1,660 square miles of drainage area and serves as the primary tributary for the largest lake in eastern Oklahoma, Tenkiller Ferry Reservoir. The Illinois has historically represented an area of significant economic importance and ecological convergence between the hilly Ozarks and the southern plains. The watershed of the Illinois River comprises five counties in Oklahoma and Arkansas, providing more than 100 miles of recreational opportunities. The Illinois River system consists of the Illinois and its tributaries, Flint and Baron Fork creeks, both of which are major tourist destinations for the south-central United States and provide a substantial portion of tourism income for the …

Island 37 is a stretch of land that is in the legal possession of the State of Tennessee but is physically joined to Arkansas. Because competing claims of jurisdiction left it in something of a legal void, Island 37 became, in the early twentieth century, an outpost for bootleggers and other criminals. Police action taken against those criminals resulted in one of the many U.S. Supreme Court cases regarding ongoing boundary disputes between Arkansas and Tennessee. The Mississippi River is a dynamic waterway, often cutting new channels and thus either forming islands or causing former islands to merge with the eastern or western banks. The legal principle of avulsion holds that land cut off by the river from one state …