The largest river in Tennessee is the Mississippi River, which forms the western border of the state. The Hatchie River is among the smaller tributaries that drain West Tennessee and flow into the Mississippi.
The state’s two most important rivers are the Cumberland and Tennessee Rivers. The Cumberland River flows through Nashville  and along the north-central portion of the state. The Tennessee River flows in a U-shape, first flowing south through East Tennessee, through Knoxville  and Chattanooga, and then northward, defining the boundary between Middle and West Tennessee. Both the Cumberland and the Tennessee Rivers empty into the Ohio River, which flows to the Mississippi.
All but one of Tennessee’s major lakes are man-made, having been created by the Tennessee Valley Authority during the last century. The lone exception to this is Reelfoot Lake in northeastern Tennessee, which was formed from the 1811 New Madrid earthquake when the mouth of what had been Reelfoot Creek was closed off and the creek’s water spread out to cover the surrounding land.