Aerial photo taken on Oct. 10, 2018 shows a view of the Badaling section of the Great Wall in the Badaling red leaf scenic area in the Yanqing District of Beijing, capital of China. China's National Cultural Heritage Administration has vowed to strengthen the protection of the Great Wall, which is more than 21,000 km long. The Great Wall, a UNESCO World Heritage Site, consists of many interconnected walls, some dating back 2,000 years. (Xinhua/Wang Tiezhong)