Chifeng (), also known as Ulanhad ( (Улаанхад хот), Ulaɣanqada qota, , "red cliff"), is a prefecture-level city in Southeastern Inner Mongolia, People's Republic of China. It borders Xilin Gol League to the north and west, Tongliao to the northeast, Chaoyang (Liaoning) to the southeast and Chengde (Hebei) to the south. The city has a total administrative area of and as of the 2020 census, had a population of 4,035,967 inhabitants (4,341,245 in 2010). However, 1,175,391 of those residents lived in the built-up (or metro) area made of the 2 urban districts of Hongshan and Songshan, as Yuanbaoshan is not conurbated yet. However, a large part of Songshan is still rural and Yuanbaoshan is a de facto separate town 27 kilometers away from the core district of Chifeng. The city was the administrative center of the defunct Ju Ud League (; ). History According to archeological studies, human occupation of the Chifeng area can be traced back at least ten thousand years, and Neolithic cultural history can be traced back nearly eight thousand years. Representative ruins and relics of Hongshan Culture, Grassland Bronze Culture, Khitan Liao Culture and Mongol-Yuan Culture have been discovered in Chifeng. The ruins of an ancient village, named Xinglongwa, and the biggest jade dragon unearthed in the area are noted as "the first village" and "the first dragon" by some. The discovery of ruins and relics of ancient cultures have come from more than 6,800 sites. Named after Chifeng's Hongshan District, Hongshan Culture was a Neolithic culture in northeastern China, whose sites have been found mainly in Chifeng, and dated from about 4700 to 2900 BC. Chifeng was the political, economic and cultural center of the Liao Dynasty, therefore, the amount of ruins and relics of the Liao Dynasty in Chifeng is ranked the most important in China. During the Qing Dynasty, today's Chifeng region was under the administration of 'Ju Ud League', one of the six original Leagues in Inner Mongolia. Mongolian Banners (county level regions) were organized into conventional assemblies at the league level. In republican era, Chifeng was under the administration of Rehe Province, along with parts of today's Liaoning and Hebei including Chaoyang and Chengde. After the Mukden Incident in 1931, the Japanese puppet state Manchukuo was established in Hsinking (today's Jilin provincial capital Changchun), and Juud League was captured by Manchukuo in 1933. Chifeng was established as the third largest city