The former Onagawa Police Box is a two-story reinforced-concrete building whose foundation was ripped out of the ground by the receding tsunami wave produced by the Greart East Japan Earthquake. It is one of the rare cases in the world where a reinforced-concrete building collapsed or was topped over by a tsunami. 

Local authorities decided to preserve the site in order to pass on the memories and lessons of the disaster, highlight the progress of reconstruction, and ensure that future generations will not experience the same grief. 

On the wall surrounding the former police box, panels describing the town before the earthquake, the damage caused by the disaster, and the process of the reconstruction are displayed.