Tah Khana. The Badshah Nama mentions the subterranean chambers below the building of the Diwan-i-Khas whose walls were nicely polished and painted in gold. It contains two cisterns, one is fed by a waterfall and the other larger one is connected with it by a water channel which conveyed water to it from the former. The grand platform or the throne terrace attached to the aiwan measures 123 ft. long 97 ft. broad under whose chambers ashrafis (gold coins) were stored. These underground chambers were also used by royal ladies during the summer season as a retreat from the unbearable heat.