Guardians of a snowy territory

The patrolling soldiers watch the train passing by. A squadron of the fourth contingent of People's Armed Police in Qinghai province is based in Kunlun Mountains, which is 4,772 meters above sea level. The average temperature here is minus 10 degrees Celsius and the oxygen content in air is 40 percent of inland. People here have to fight against the arduous weather. (Xinhua/Ma Ding)