Iwanuma is a city situated in the Miyagi Prefecture of Japan. It covers a total area of 60.45 square kilometers (23.34 square miles). As of March 31, 2020, the city had an estimated population of 43,946 residents living in 18,062 households, resulting in a population density of 730 persons per square kilometer.
The city is historically significant for its location at the convergence of two ancient roads: the Tōkaidō and the Rikuzen-Hama Kaidō.