Located in the Northwest Region of the state, in the Solomon River Drainage Basin. Stretching from the high plains of western Kansas, from which the Solomon River gets its start, the Solomon Valley slopes gently down as the river flows east along Highway 24. The river is about 300 miles long. Once also known as the Nepaholla river, is formed by its two branchesthe N and S both of which rise in Thomas County, within 10 Mi. of each other, and for the first 10 Mi. flow almost parallel to each other at a distance of not over 4 or 5 Mi. The N branch flows in a NE direction through Thomas County, the NW corner of Sheridan County, the extreme SW corner of Decatur County, the S portion of Norton County and Phillips County, the SW corner of Smith County and the NE corner of Osborne County and into Mitchell County. The S fork flows almost due E through Thomas County, Sheridan County, Graham County, Rooks County and Osborne County and unites with the other branch about 2 Mi. East of the West line of Mitchell County.