File photo taken on June 5, 2020 shows a stone tablet unearthed from the remains of the Qingpingbao castle, located in Jingbian county, Yulin city of northwest China's Shaanxi province. The remains of a Great Wall castle dating back to the Ming Dynasty (1368-1644) were discovered in Northwest China's Shaanxi province, said the Shaanxi Academy of Archaeology Tuesday. Architectural relics, including two courtyards, were found at the remains of the Qingpingbao castle.[Photo/Xinhua]