I want to know the answer to the following question:
where did the trade route pass through?
All the background I'm provided with is that "Tsai writes that shortly after the visit by Deshin Shekpa, the Yongle Emperor ordered the construction of a road and of trading posts in the upper reaches of the Yangzi and Mekong Rivers in order to facilitate trade with Tibet in tea, horses, and salt.". Is that enough to answer the question?