Upper Mustang Trek takes trekkers to the northern part of Nepal which shares the border with Tibet, Autonomous Region of China. The site has close cultural and religion tie with Tibet since the time of yore. The almost entire population of this area follow Tibetan Buddhism as most of the people leaving here are descendants of Tibet. The deserted part from Tibetan part to the south of Kagbeni is known as Upper Mustang. The high mountains here block monsoon rain and due to this, it is considered a rain shaded area..