Built
Under Meng Tian, from 212 BC
The Qin Direct Road was a national military tr...
The Qin Direct Road was a national military trunk line built on the order of the First Emperor under general Meng Tian: from Yunyang near the Qin capital (today's Chunhua, Shaanxi) north across the loess plateau and the Ordos grasslands to Jiuyuan (today's Baotou, Inner Mongolia) — some seven hundred kilometers, up to sixty meters wide. 'Cut through mountains, fill the valleys, run it straight': avoiding river valleys and climbing the ridgelines in a straight line earned it the name 'Direct Road' — an expressway of antiquity. On it, Qin cavalry could reach the Yinshan front in three days and nights; it shaped frontier defense, imperial edicts, migration and ethnic fusion, and stretches of its compacted bed still bear little grass today.
Ancient roads followed river valleys for water and grade; the Direct Road did the opposite — cutting through mountains, filling the gullies, drawing a nearly straight military line across the loess ridges. The reason was one word: speed. Xiongnu cavalry could reach the Guanzhong heartland in ten days; Qin cavalry had to be faster — seven hundred kilometers in three, straight to the front.
The engineering still astonishes: the bed was rammed in layers of loess, treated — tradition says with salt, alkali and heat-hardened earth — so tightly that two millennia later the surface still resists vegetation, 'a thousand li and through.' From the air over the Shaanxi–Gansu border a straight earthen line is still plainly visible: the First Emperor's engineering obsession, visible to the naked eye.
The road was first of all a frontier system: Qin planted thirty-four counties along the Yinshan, and the Direct Road was its supply and reinforcement line — Meng Tian 'drove the Xiongnu seven hundred li north, and they dared not look south to pasture,' half the credit on the road. It was a road of edicts too: an imperial rescript reached Jiuyuan in three days — imperial administration outrunning the hoof for the first time.
Roads bring people: garrisons, settlers and exiles spread along it; farming technique entered the Ordos; steppe horses and furs came down to Guanzhong. A military expressway became, almost by accident, the frontier where farming and nomad civilizations met — Emperor Wu of Han later toured north on it, and Wang Zhaojun's journey out of the passes followed its way.
After the Qin fell the road served for centuries more: Emperor Wu toured north on it in the Yuanfeng era; into the Tang it remained one of the northern ways out of Chang'an; after the Song it faded. It raised no stone to record itself — only five characters in the Records of the Grand Historian: 'a thousand and eight hundred li.'
From 1975 the historical geographer Shi Nianhai reconstructed the road's course, and the expressway forgotten for two thousand years returned to the map. Today the site is a national protected monument; hikers walk the rammed bed between loess gullies and wind — a national project of the Qin, still speaking for it.