Aerial photo taken on April 19, 2019 shows the Tiantian Mountain and the Yongning Pavilion of the 2019 Beijing International Horticultural Exhibition (Expo 2019 Beijing) in Yanqing District of Beijing, capital of China. The 2019 Beijing International Horticultural Exhibition is slated to kick off on April 29, 2019. (Xinhua/Ju Huanzong)