Bayan-Ölgii Province
At approximately , the borders of Russia, China, Mongolia and Kazakhstan intersect in the Altai Mountains. Mongolia and Kazakhstan are separated by a 55km stretch of the Sino-Russian border between the Altai Republic, a federal subject of Russia, and Altay Prefecture in the Xinjiang Uyghur Autonomous Region of China. To the east, Tavan Bogd Uul in Bayan-Ölgii Province, Mongolia, marks the end of the Sino-Russian border. To the west, is Kazakhstan's East Kazakhstan Province.