Based On the Shivagrha inscription, a public water project to alter the class of a river near Shivagrha temple was carried out for the duration of the development on the temple. The river, determined because the Opak River, now runs north to south about the western side with the Prambanan https://panchmukhihanumaninsydney.blogspot.com/2024/09/discovering-rich-heritage-of-indian.html