Aerial photo taken on Sept. 22, 2017 shows the autumn scenery of the Saihanba forest in Weichang Manchu and Mongolian Autonomous County in Chengde City, north China's Hebei Province. Saihanba is a vast forest covering nearly 75,000 hectares. It was a piece of barren land 55 years ago, but decades of hard afforestation efforts turned it into an important ecological shield for Beijing and Tianjin. (Xinhua/Liu Huanyu)