National Geographic : 1923 Feb
0o Photograph by J.T.McGarvey CAMEL, CARAVAN, WITH SUPPLIES, DESCENDING KALGAN PASS Several caravan routes unite at Kalgan, which is a gateway to Mongolia and a great trading center forChina and Siberia. Over 1oo,ooo camels are said to be used in transporting tea alone from Kalgan to Siberia. In the internal caravan trade no less than 1,200,000 camels and 300,000 oxcarts are employed. At Kalgan exists the very earliest, original wall, built by the Emperor Chin, contemporary of Hannibal.