Chinese archaeologists discover well-preserved section of 2,200-year-old 4-lane highway

Chinese archaeologists have uncovered a stretch of the celebrated Qin Straight Road, one of the most ambitious infrastructure projects in human history.\nUnveiled on December 9, following a 2024 survey by the Cultural Heritage Protection and Research Institute of Yulin, Shaanxi province, the discovery of a 13km (8-mile) stretch offers fresh evidence of the 2,200-year-old “highway” that once spanned nearly 900km across northern China.\nAccording to historical records, the Qin Straight Road was built under the orders of Qin Shi Huang, China’s first emperor, and completed in just five years.\nExcavations reveal sophisticated construction techniques, such as trench passes aligned in a straight line, rammed-earth slope reinforcements, compacted roadbeds and filled valleys. It averaged about 40 metres (130ft) in width – enough space for four lanes of traffic.\nHistorical records described how workers “filled valleys and levelled mountains” to create a direct north-south corridor from Xianyang, the capital of the Qin dynasty (221-207BC), in modern-day Shaanxi province, to Jiuyuan, now the city of Baotou in Inner Mongolia, enabling rapid military deployment against the Xiongnu nomads.\nThe discovery also included a small site nearby, believed to be a relay station that spanned the Qin era and its successor the Han dynasty (206BC-AD220). Ceramic fragments found there helped confirm its age and function.\n“The Qin Straight Road is the second-largest national defence project in ancient China, following the Great Wall,” according to China Cultural Heritage News, a publication under the National Cultural Heritage Administration.\nThe publication hailed the road as “the ancestor of the world’s highways”.\n\nThe discovery corroborates ancient texts and sheds new light on pre-industrial engineering, showing that China built one of the world’s first long-distance land transport networks more than two millennia ago.\nArchaeologists used satellite technology to identify the lines of potential roads that were visible in areas where greenery had been planted on what was once desert.\nAccording to Yulin authorities, the survey found well-preserved remains, including nine continuous trench sections arranged in a straight line and compacting layers of earth to strengthen the slope.\nIt also revealed multiple traces of trampled surfaces – areas compacted by foot or wheel traffic – as well as compacted roadbeds and filled valleys.\nWhile the road varied in width from 40 metres to 60 metres, its distance from surrounding mountain passes generally ranged between 50 metres and 90 metres.\nThe discovery may help to locate unconfirmed sections of the road between Yulin and Ordos, neighbouring cities that straddle Shaanxi and Inner Mongolia.\nAfter unifying six states to form China, Qin Shi Huang ordered General\nMeng Tian – a prominent military commander and the primary architect of the early Great Wall – to mobilise hundreds of thousands of soldiers and civilians to build the Qin Straight Road to streamline logistics and defend China against the Xiongnu.\nThe ancient road started at Xianyang and extended north to Jiuyuan county, present-day Baotou, passing through 14 counties.\nThe military artery became a cornerstone of the emperor’s northern defence strategy.\nDuring the Qin dynasty, the road and the Great Wall were instrumental in repelling Xiongnu invasions. The Great Wall ensured a strong and extensive defensive line, and a reliable supporting transport route was needed to efficiently deploy troops and supplies.\nAccording to the records of the historian Sima Qian in Records of the Grand Historian, construction of the Qin Straight Road began in 212 BC – the 35th year of Qin Shi Huang’s reign – and continued through the emperor’s death. Following the accession of his son, Qin Er Shi, the project reached completion in 207 BC.\nSima Qian, who travelled along the road itself, documented its starting and end points and described the process of “filling valleys and levelling mountains” to carve out the path and use massive quantities of rammed earth to ensure a level pathway across the rugged terrain.\n\n\nHowever, owing to dynastic changes and sparse historical documentation, the exact trajectory of the Qin Straight Road was eventually lost to time.\nAlthough the route was built at the height of imperial power, once that empire’s power waned it became more of a help to the nomads it was designed to combat by providing an easy route into the heart of the country for invaders.\nConsequently, there are at least three recorded instances in history where the Han people deliberately destroyed sections of the road.\nIn 1974, Chinese archaeologists uncovered a section of the road, and the search for the remaining route has continued ever since.\nIn 2009, the Qin Straight Road site in Fu county, Shaanxi province, was recognised as one of China’s top 10 archaeological discoveries.\nThe Qin Straight Road is mostly easy to trace, though the Mu Us Desert now covers much of the Yulin section, making it difficult to locate. Efforts to regreen the area only began in recent decades.\nTo address this challenge, archaeologists identified this section to the west of the Hengshan district by comparing historical and recent satellite images.\nSubsequent field surveys revealed a newly identified section of the Qin Straight Road. However, much of its surface is now obscured or has vanished, largely because of natural and human factors.\n