The Kuhistani Badakhshan Autonomous Region (Tajik: Вилояти Мухтори Кӯҳистони Бадахшон, Viloyati Muxtori Köhistoni Badaxshon; also known as Gorno-Badakhshan, after Russian: Горно-Бадахшанская автономная область, abbrev. GBAO) is an autonomous region in Eastern Tajikistan. Located in the Pamir Mountains, it makes up 45% of the land area of the country but only 3% of its population. Prior to 1895, the area of today's Gorno-Badakhshan A.R. consisted of several semi-self governing statelets, including Darwaz, Shughnun-Rushan and Wakhan, who ruled over territories that today are part of Gorno-Badakhshan A.R. in Tajikistan and Badakhshan Province in Afghanistan. The territory was claimed by the Chinese and Russian empires and the Emirate of Afghanistan. The Qing rulers of China claimed control of the entire Pamir Mountains, but Qing military units only controlled the passes just east of Tashkurgan. In the 1890s, the Chinese, Russian and Afghan governments signed a series of agreements that divided Badakhshan, but the Chinese continued to contest these borders, until it signed a 2002 agreement with the government of Tajikistan.
Gorno-Badakhshan Autonomous Region was created in January 1925. It was attached to Tajik Soviet Socialist Republic after the republic's creation in 1929. During the 1950s, the native inhabitants of Gorno-Badakhshan, including many ethnic Pamiris, were forcibly relocated to southwestern Tajikistan. Gorno-Badakhshan absorbed some of the territory of the Gharm Oblast when that territory was dissolved in 1955. GBAO covers all the eastern part of the country and borders the Xinjiang Uyghur Autonomous Region of China in the east, the Badakhshan Province of Afghanistan in the south, and Osh Region of Kyrgyzstan in the north. Within Tajikistan the region's western border is with the Districts of Republican Subordination (DRP) and the tip of its south-western finger (Darvoz District) borders on Khatlon Region. The highest mountains are in the Pamirs (ancient Mount Imeon), which is known as the roof of the world, and three of the five 7,000 meter summits in formerly Soviet Central Asia are located here, including Ismoil Somoni Peak (formerly Communism Peak, and, before that, Stalin Peak; 7,495 m), Ibn Sina Peak (formerly Lenin Peak, and still known by that name on its Kyrgyz flank; 7,134 m), on the border with Kyrgyzstan, and Peak Korzhenevskaya (7,105 m).
The postal services provided in GBAO is by Tajik Post. There are no special postage stamps for GBAO, All Tajik stamps are valid for postage. In 2018, a series of stamps issued by Tajik post, depicting “Regions of Tajikistan”. On the envelope the “GBAO” stamps can be seen, and the provincial related buildings too.