This historical monument belonging to the period of Caucasian Albania, belonging to the IV-IX centuries, is located at the bottom of the mountain in the village of Kosalar, Lachin. There is an ancient “observation tower” on the top of this mountain. Information about the existence of underground passages from the castle to the “Agoglan” castle was obtained for the first time in 1985. However, traces of these underground passages that existed inside the castle were not discovered in the period before the Armenian occupation. But in 2009, Armenian archaeologists discovered three wells inside the complex to go down to this passage.