During Ilkhanid era to maintain communication between the individual khanates in the empire, and between these khanates and the khan, and throughout the empire, a rapid and effective post system, YAM, was organized. A continues change of mounts, made possible by the enormous numbers of horses available to them allowed some of the riders to travel over two hundred miles in one day. There were three main classes in the postal system: "second class", carried by foot-runners; "first class", carried on horseback; and "His Majesty's Service", carried by non-stop riders who changed horses but not riders. This may have lasted long after the empire had ceased to exit. Undoubtedly, the trade had played an important role in Ikhanid dynasty. In this way, facilitated safe trade roads would be inevitable. Legends has it that an unprotected young female could take a sack of gold safely from Don River to Khanbalik.
The Yam Caravanserai is one of the few remaining of these royal Yams which had been reused during Safavid era in order to improve the economic plans of king Abbas the great
