阿武隈川
Nihonmatsu is located in the Nakadōri section of Fukushima prefecture, between the cities of Fukushima and Kōriyama. It is approximately 250 km from central Tokyo. Nihonmatsu's western border consists of the Adatara mountain range. The Abukuma River runs through the eastern part (forming the border between the former towns of Adachi and Tōwa), flowing from south to north.