Investigating the legal status of border demarcation in border rivers (with emphasis on construction facilities in the Aras border river)

Determining the border line between countries is, on the one hand, the main factor of peace and, on the other hand, the indicator of independence, and these two factors, in turn, create an atmosphere in which security prevails. This research has been done using descriptive-analytical method.The findings show that in the absence of agreement between the parties regarding the border line on the construction facilities on the Rahel border rivers, it is that the border line continues vertically on the waterway. This is consistent with the general theory that the boundary divides the sovereignty of countries not only on the ground, but also on the bed and at the air. In addition, the solution, consisting of the vertical extension of the boundary line over waterways, avoids problems that may arise from two different boundaries in adjacent geometric maps.The present study indicates the method of determining the border line on the bridges constructed on the Aras River. On the border bridges on the Aras River, according to the proposal of this research, the border line on the bridge compared to the old Julfa bridge will be changed by 44.13 meters in favor of Islamic Iran.