The 2nd Century BCE: A Formal Beginning
Following Zhang Qian’s revelations, the Han Dynasty began to militarily secure the paths leading westward. By roughly 114 BCE, the Emperor had pushed the boundaries of the Great Wall further into the desert and established the Hexi Corridor. This corridor served as a protected "highway" through which Chinese silk could safely travel to the West in exchange for horses, gold, and grapes. This period marks the transition from incidental, local bartering to the established, state-sanctioned Silk Road trade that would define the next 1,500 years of human history.

Pre-Silk Road Precedents and the Jade Road
While the official answer to when was the silk road established focuses on the Han Dynasty, it is important to acknowledge that the tracks were not laid on fresh ground. Archaeologists have found evidence of the "Jade Road," a series of routes used as early as 5000 BCE to transport nephrite jade from the Kunlun Mountains to the Chinese heartland. Furthermore, the "Lapis Lazuli Road" connected Mesopotamia with the Indus Valley in the 3rd Millennium BCE. The Silk Road did not invent trade; rather, it integrated these existing regional paths into a singular, grand network of continental exchange.https://www.glamourtrains.com/....en/train-routes/silk