The complex contains a deep, circular, brick-lined pit almost 10 meters in diameter resembling an ancient dungeon found at the heart of the old building. Clay is the preferred material used on the walls of the building because it can get very hot in Yazd.
The dome of Iskandar Prison is made of raw clay and is decorated with plaster works and golden and azure watercolor. The material used in much of the building is clay, however, it has been restored with bricks in the past. Each side of the domed tower is almost 9 meters long and it rises almost 18 meters tall