Musamman Burj, Agra Fort On the east side of the fort, this octagonal pavilion looks out across the Jumna River and countryside, and downstream to the Taj Mahal. It is said to be the tower where Shah Jahan was imprisoned. Next to the Burj in the photo left foreground is the rear of the Khass Mahal and its adjoining pavilions. Below are fortifications and the riverbank. The river was originally higher, reaching up to the base of the walls.