Photo taken on May 27, 2016 shows the scenery of Cuckoo Lake in Arxan National Forest Park, North China’s Inner Mongolia autonomous region. [Photo/Xinhua]

Aerial photo taken on May 25, 2016 shows the scenery of a lake surrounded by forests in Arxan Mountain, North China’s Inner Mongolia autonomous region.[Photo/Xinhua]

The setting sun casts an orange glow on Tianchi Lake in Arxan Mountain, North China’s Inner Mongolia autonomous region, May 25, 2016.[Photo/Xinhua]

The setting sun casts an orange glow and is reflected on the surface of a lake in Arxan Mountain, North China’s Inner Mongolia autonomous region, May 27, 2016.[Photo/Xinhua]

Horses graze in Arxan Mountain, North China’s Inner Mongolia autonomous region, May 25, 2016.[Photo/Xinhua]