Silk Road Relay Station System

Timeline

1. c. -200–900Chang'an–Dunhuang–Samarkand · Silk RoadThe Han dynasty set up garrison posts, beacon towers, and courier lodges along the Hexi Corridor; the Tang relay system regulated distances, horses, and lodging standards. Central Asian Sogdian merchants established trading lodges (caravanserais) in Samarkand, Kashgar, and elsewhere, providing warehousing and escort for caravans and forming a segmented relay transport model.
2. 1031–1040Yanzhou (present-day Yan'an)–Xiazhou trade route · Northwest ChinaNorthern Song built forts and courier posts along the Song–Xia border; Western Xia controlled Hexi Corridor relay stations where caravans rested and changed horses. Liao, Song, and Xia border-market trade required designated passes; the relay system also handled official document transmission and caravan credential checks, while Karakhanid relay stations on the northern Tianshan connected with Western Regions cities.
3. c. 900–1200Khurasan trade route · KhurasanSince the Abbasid dynasty, large caravanserais (رباط/rabat, کاروانسرا) were built along Persian and Central Asian trade routes, offering courtyards, stables, water, and security. Under the Seljuks relay station density increased, forming a node–corridor structure with the markets of Baghdad, Isfahan, and other cities, supporting transcontinental trade.
4. c. 1206–1400Shangdu–Dadu post road · Mongolian PlateauThe Mongol Empire unified Central Plains relay stations, Persian yam, and steppe örtöö into the jam system, regulating mounted-horse credentials, horse-change distances, and lodging provisions. Under Kublai Khan, Eurasian post roads were linked through; travelers such as Marco Polo recorded their efficiency, making it one of the most developed overland communication networks of the premodern world.