Postal courier Cering Quba carries a bag of mails to the township branch of China Post in Pumaqangtang Township of Nagarze County in Shannan, southwest China's Tibet Autonomous Region, July 23, 2018.

Postal courier Cering Quba loads mails and packages onto a postal van in Nagarze County in Shannan, southwest China's Tibet Autonomous Region, July 23, 2018.

Motorbike courier Gesang Cering (L) chats with his senior workmate Cering Quba in Pumaqangtang Township of Nagarze County in Shannan, southwest China's Tibet Autonomous Region, July 27, 2018. In Pumaqantang Township, the highest township in China, working as a postal service staff means delivering mails to addresses at altitudes of 5,000 meters and above. Gesang Cering, 29, is a motorbike courier with the local township branch of China Post. Twice a week, Gesang calls on the plateau villages under the township on a 160-km route, coping with extreme oxygen and temperature conditions. Despite its harsh geography, Tibet Autonomous Region has substantially improved the local postal service over the four decades since China's reform and opening up. By the end of 2017, the postal road network had managed to cover all towns and counties within the autonomous region. (Photos: Xinhua)

Gesang Cering delivers a mail package to a client in Pumaqangtang Township of Nagarze County in Shannan, southwest China's Tibet Autonomous Region, July 27, 2018.

Gesang Cering performs a mail delivery task in Pumaqangtang Township of Nagarze County in Shannan, southwest China's Tibet Autonomous Region, July 23, 2018.

Gesang Cering performs a mail delivery task in Pumaqangtang Township of Nagarze County in Shannan, southwest China's Tibet Autonomous Region, July 27, 2018.

Gesang Cering (1st L) and his workmate Cering Quba (2nd L) talk with clients in Pumaqangtang Township of Nagarze County in Shannan, southwest China's Tibet Autonomous Region, July 27, 2018.

Gesang Cering performs a mail delivery task in Pumaqangtang Township of Nagarze County in Shannan, southwest China's Tibet Autonomous Region, July 27, 2018.

Gesang Cering fixes a postal mail bag to the rear of his motorbike before setting off for work in Pumaqangtang Township of Nagarze County in Shannan, southwest China's Tibet Autonomous Region, July 23, 2018.

Gesang Cering (R) and his workmate Cering Quba (L) talk with a villager in Pumaqangtang Township of Nagarze County in Shannan, southwest China's Tibet Autonomous Region, July 27, 2018.