Aerial photo taken on April 18, 2017 shows the scenery of White Horse Monastery in Luoyang City, central China's Henan Province. (Xinhua/Chen Jianli)

Aerial photo taken on April 18, 2017 shows the scenery of Longmen Grottoes in Luoyang City, central China's Henan Province. (Xinhua/Li An)

Aerial photo taken on April 17, 2017 shows the scenery of Luoyang City, central China's Henan Province. (Xinhua/Jin Liangkuai)

Aerial photo taken on April 17, 2017 shows a night market in central China's Henan Province. (Xinhua/Chen Jianli)

Aerial photo taken on April 18, 2017 shows the night scenery of Luoyang City, central China's Henan Province. (Xinhua/Li An)

Aerial photo taken on April 17, 2017 shows the scenery of Longmen Grottoes in Luoyang City, central China's Henan Province. (Xinhua/Li Bo)

Aerial photo taken on April 17, 2017 shows the scenery of Luoyang City, central China's Henan Province. (Xinhua/Chen Jianli)

Aerial photo taken on April 18, 2017 shows the night scenery of Luoyang City, central China's Henan Province. (Xinhua/Li Bo)

Aerial photo taken on April 18, 2017 shows the night scenery of White Horse Monastery in Luoyang City, central China's Henan Province. (Xinhua/Li An)

Aerial photo taken on April 18, 2017 shows the scenery of the Yellow River Xiaolangdi scenic zone in Mengjin County of Luoyang City, central China's Henan Province. (Xinhua/Li Bo)

Aerial photo taken on April 17, 2017 shows the night scenery in Luoyang City, central China's Henan Province. (Xinhua/Li An)