The river forms most of Arkansas's eastern border
The 
Tennessee State line east of Bristol shifts to the South because Smith .... 
Tennessee's boundary with Arkansas is where the channel of the Mississippi 
River was in... [DOC] [TLE] Geography of Missouri - World Atlas [PAR] In the west, south of the Missouri River, the Osage Plains stretch to its border with 
... (also covering portions of Arkansas, Illinois, Kansas and Oklahoma) dominates 
the ...