The upper reaches of the Yellow River flow some 900 km in eastern Gansu. To the west, the long and narrow Hexi Corridor — "Hexi" means "west of the Yellow River" in Chinese — has served, since ancient times, as a key route linking the Central Plains with the country's western regions and beyond.

Wang notes that the prehistoric routes of painted pottery transmission through the Hexi Corridor largely overlapped with the ancient Silk Road, as both relied on the same geographical artery.

Building on this geographical and archaeological reality, scholars have named the east-to-west expansion of early Chinese culture — represented by painted pottery — the "Painted Pottery Road".

Han Jianye, professor at the School of History, Renmin University of China, has studied this topic for years and published a collection of essays on it.

According to Han, painted pottery from present-day Shaanxi and Gansu provinces spread westward from the 4th to the 1st millennium BC. Divided by the Qinghai-Tibet Plateau, the routes branched into a northern path — spreading to Central Asia and beyond via Xinjiang -and a southern path toward the Kashmir region.

"The Painted Pottery Road was the primary channel for early cultural exchanges between China and the West and can be regarded as a precursor to the Silk Road," he writes.