Built in 1032, the city thrived under the rule of the Tangut-led Western Xia dynasty, which occupied the area round the Hexi Corridor, a stretch of the Silk Road on the trade route between North ...

During our summer trip to the Hexi Corridor, part of the ancient Silk Road, in June, my family and I drove through Shandan county. We were puzzled by a stretch of earthen "walls" along the way.