最上川
Kawanishi is located in the southwest of the Yonezawa Basin. There are two major rivers, the Mogami River and the Omonogawa River, running along the town's borders. The literal meaning of Kawanishi is "west of the river", which refers to its location west of the Mogami River. Also, there are two minor rivers, the Inukawa and the Kurokawa, running through the town.