Runners start off at Columbia168 Ultra-Trail Chanllenge in the Chongli District of Zhangjiakou City, north China's Hebei Province, July 14, 2017. Two years after Beijing and Zhangjiakou successfully bid to host the 2022 Winter Olympics, Chongli District, where most skiing events will be held, experienced a busy and colorful summer. (Xinhua/Zhang Gang)
