A relic stone with carvings resembling a human face is found by archeologists from the Shaanxi Provincial Institute of Archaeology. The discovery was made at the Shimao site near Gaojiabao town in Shenmu County in Shaanxi Province on October 10, 2015. The relics belong to the largest city discovered in China that dates back 4,000 years. Photo: provided by Shaanxi Provincial Institute of Archaeology

A stone wall is unearthed by archeologists from Shaanxi Provincial Institute of Archaeology. The discovery was made at the Shimao site near Gaojiabao town in Shenmu County in Shaanxi Province on October 10, 2015. The relics belong to the largest city discovered in China that dates back 4,000 years. Photo: provided by Shaanxi Provincial Institute of Archaeology

More relics have been found from Shimao site near Gaojiabao town at Shenmu County in Shaanxi Province on October 10, 2015. The relics belong to the largest city discovered in China that dates back 4,000 years. Photo: provided by Shaanxi Provincial Institute of Archaeology