Babk is a fort located at the top of a mountain close to Kaleybar City in East Azerbaijan Province which is attributed to Babak Khorramdin, the Iranian commander who rebelled against Abbasids after Abu Moslem Khorasani.
This pick is placed in 2300meters height and it is related to Sassanid Period. Saeed Nafisi, the contemporary historian and writer, has mentioned to the remains of a fort located in 21parasang of Ardabil, namely Ghale Jomhour (Republic Fort). In addition, among other writers and scholars who have referred to Babak Fort, Ahmad Kasravi should be mentioned; he describes a fort named Baz in the south of Aras River, at the heart of the current Ghara Dagh and in the north of Ahar City, slightly eastward.
Sometime before Sassanid Period, apparently in Achaemenid Empire, a tribe named Kadusian, the habitants of the southwestern shores of Caspian Sea, lived there and they often fought with Achaemenids. According to historians, Kadus tribe is the equivalent of the current Talsh tribe. However, there is no evidence of Baz in historical documents between Sassanid period and the 8th century AD.
One has to pass a difficult rout in order to reach the top of mountain and the place of the Fort. There exists a narrow passage before the entrance. Towers in two sides of the entrance is the headquarters of guards. The entrance is the only way to enter the fort because of the security issues.
Babak Fort has a multi-storey structure in which the main hall has been surrounded by seven rooms all of them ends up in the hall.
The only way to reach the upper floors is a staircase located in the northwestern side of the fort. Other parts like cisterns and rooms are also placed here. The roof of this cistern has been established by barrel and rib vault.
One interesting issue about the materials used in the building of cistern is the usage of mortar in order to prevent the rain and snow water penetration. Therefore, in rainy and snowy seasons the tank become full of water that they use it in summer.