制限区域
The Darkhads and their descendants faithfully carried out their assignment for more than 700 years, from the Khan’s death in 1227 until the establishment of the Mongolian People's Republic (a satellite state of the USSR) in 1924. The Soviets feared that if the region were made publicly accessible memories of Genghis Khan would encourage Mongolian nationalism, so they declared the land a 'Highly Restricted Area' and cordoned off 10,400 square-kilometers of surrounding land.