GBAO (Gorno-Badakhshan Autonomous Oblast) starts at Kalaikhum and ends at the Kyrgyz border at Kizil-Art Pass. This region of Tajikistan is a special border zone and an additional permit is required to travel there.
From 2004, the GBAO permit is issued on a slip of paper issued by OVIR (the Department of visas and registration of foreign citizens). Previously, the permit was stamped into your passport.
The GBAO permit will list the regions in Gorno-Badakhshan that you are allowed to visit, which will be some or all of: Darvaz, Vanj, Rushan, Shugnan, Ishkashim, Roshtqala and Murghab. Sometimes it may say "all regions". Make sure that all the regions you plan to visit are listed. In particular, if you plan to travel in the Wakhan river valley the GBAO permit must have "Ishkashim" listed, or the Russian border guards will not permit you to pass.
Even with the permit, you do not have unrestricted access to travel in Gorno-Badakhshan. Specifically, you need additional permission to visit Lake Sarez, Lake Zorkul, and some regions near to the Chinese or Afghan borders.
You can apply for the appropriate sanctions (permission) for visiting a border zone at the Department of visas and registration of foreign citizens (OVIR) of the Ministry of Internal Affairs
, and Sarez lake permission – at the Committee of Emergency Situations and a civil defense.