Mongol Yam Relay System

Timeline

1. c. 1206–1227Mongolian Plateau · Mongolian PlateauAfter unifying the Mongol tribes, Genghis Khan expanded the steppe tradition of rapid courier relay and horse-changing into an empire-wide station network, setting up stations for envoys and troops to change horses and resupply, and regulating passage with paiza (such as silver and gold tablets), providing a high-speed overland route for western campaigns and internal administration.
2. c. 1229–1241Central Asian steppe corridor · Central AsiaDuring Ögedei Khan's reign, the relay stations were greatly expanded westward from the Mongolian Plateau into Central Asia, forming a trunk line across the steppe; besides delivering documents, stations also conscripted labor, collected supplies, and received envoys, becoming physical nodes of the empire's administrative reach.
3. 1271–1360Main lines from Dadu across Eurasia · North ChinaThe Yuan dynasty formally named the relay system zhanchi, established a central supervisory agency in Dadu, set up land and water stations across the realm, and regulated distances, horse quotas, and envoy treatment; the station network overlapped with Silk Road trade routes, giving Eurasian overland routes unprecedentedly dense traffic and information flow in the 13th–14th centuries.
4. c. 1368–1400Various segments of Eurasian overland routes · EurasiaAfter the fall of the Yuan dynasty, the unified transcontinental relay system broke apart with political fragmentation; although the khanates retained local courier services, distance standards, paiza systems, and maintenance capacity varied widely, and the peak of integrated Eurasian overland transport came to an end.