Arg-e-Bam is the most prominent property in Bam City, Kerman Province inscribed on the World Heritage List. Despite diverse studies by prominent archaeologists, our knowledge of its original urban configuration is still trivial. The second gate—entrance to the citadel—in particular requires further studies. The collapse of appended layers in the earthquake of 2003, revealed remains, which have shed doubt on the original formation of this gate. This paper examines the original formation of the second gate based on a study of historical texts, as well as findings of new excavations. It is demonstrated that original second gate was located in the tower some 50 meters from the current gate. The original gate was built at the time of construction of the wall in late Seleucid or early Parthian period and was in place until mid-Qajar period. During the uprising of Agha Khan between 1251~1257 L.A.H., Bam was under siege and the citadel fortifications were drastically damaged. After the siege, Arg-e-Bam was used as a military base with its commander residing in the citadel. To facilitate access to the forces in the stable area, the original gate was closed and the current gate was built in its place.