Longnan's position on the route between the Guanzhong plain and Sichuan gave it strategic importance that long predates the Silk Road. The roads the Qin state pushed through these mountains — the Chencang and Baoxie routes — were the arteries through which armies, merchants, and officials moved between the north China heartland and the south. Inscribed cliff faces in several locations along these routes record the labour of construction and the names of officials who oversaw the work.
The remnants are scattered and require some research to locate, but the landscape itself tells the story: these were genuinely difficult mountains to cross, and the ingenuity required to build viable roads through them was considerable. Local guides and county tourism bureaus can direct serious visitors to the best-preserved sections and inscriptions.