The Arkansas River flows southeast across the state between the Ozark plateau and the Ouachita Mountains and runs down to the southern and eastern plains to empty into the Mississippi River. The other rivers of the state also flow generally SE or S to the Mississippi; these include the Saint Francis (which forms part of the E Missouri line), the White River, the Ouachita, and the Red River (which forms part of the Texas line). The state's transportation network is based on rivers as well as roads, railroads, and air travel. The 440 mi (708 km) Arkansas River Navigation System links Oklahoma and Arkansas to the Mississippi River.
The climate of Arkansas is marked by long, hot summers and mild winters. The state's many lakes and streams and its abundant wildlife provide excellent hunting and fishing. The mineral springs at Hot Springs also attract many visitors to Arkansas, where tourism is an important industry.