Aerial photo taken on Oct. 21, 2018 shows a view of Danxia landform at Wangjiawan of Pingqiao Town in Ansai District of Yan'an, northwest China's Shaanxi Province. Danxia landform is a unique type of geomorphology formed from red-colored sandstones and characterized by steep cliffs. (Xinhua/Tao Ming)
Aerial photo taken on Oct. 21, 2018 shows a view of Danxia landform at dusk at Wangjiawan of Pingqiao Town in Ansai District of Yan'an, northwest China's Shaanxi Province. Danxia landform is a unique type of geomorphology formed from red-colored sandstones and characterized by steep cliffs. (Xinhua/Tao Ming)
Aerial photo taken on Oct. 21, 2018 shows a view of Danxia landform at Wangjiawan of Pingqiao Town in Ansai District of Yan'an, northwest China's Shaanxi Province. Danxia landform is a unique type of geomorphology formed from red-colored sandstones and characterized by steep cliffs. (Xinhua/Tao Ming)
Aerial photo taken on Oct. 21, 2018 shows a view of Danxia landform at Wangjiawan of Pingqiao Town in Ansai District of Yan'an, northwest China's Shaanxi Province. Danxia landform is a unique type of geomorphology formed from red-colored sandstones and characterized by steep cliffs. (Xinhua/Tao Ming)
Aerial photo taken on Oct. 21, 2018 shows a view of Danxia landform at Wangjiawan of Pingqiao Town in Ansai District of Yan'an, northwest China's Shaanxi Province. Danxia landform is a unique type of geomorphology formed from red-colored sandstones and characterized by steep cliffs. (Xinhua/Tao Ming)
Photo taken on Oct. 21, 2018 shows a view of Danxia landform at Wangjiawan of Pingqiao Town in Ansai District of Yan'an, northwest China's Shaanxi Province. Danxia landform is a unique type of geomorphology formed from red-colored sandstones and characterized by steep cliffs. (Xinhua/Tao Ming)
Photo taken on Oct. 21, 2018 shows a view of Danxia landform at Wangjiawan of Pingqiao Town in Ansai District of Yan'an, northwest China's Shaanxi Province. Danxia landform is a unique type of geomorphology formed from red-colored sandstones and characterized by steep cliffs. (Xinhua/Tao Ming)
Aerial photo taken on Oct. 21, 2018 shows a view of Danxia landform at Wangjiawan of Pingqiao Town in Ansai District of Yan'an, northwest China's Shaanxi Province. Danxia landform is a unique type of geomorphology formed from red-colored sandstones and characterized by steep cliffs. (Xinhua/Tao Ming)