Aerial photo taken on March 27, 2019 shows the site of the International Horticultural Exhibition 2019 Beijing China (Expo 2019 Beijing) in Yanqing District of Beijing, capital of China. (Photos: Xinhua)

Computer-integrated aerial photo taken on March 26, 2019 shows the Guirui Theater in the center at the site of the International Horticultural Exhibition 2019 Beijing China (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.

Aerial photo taken on March 27, 2019 shows the site of the International Horticultural Exhibition 2019 Beijing China (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.

Stitched aerial photo taken on March 26, 2019 shows the site of the International Horticultural Exhibition 2019 Beijing China (Expo 2019 Beijing) in Yanqing District of Beijing, capital of China.

Aerial photo taken on March 27, 2019 shows the International Pavilion at the site of the International Horticultural Exhibition 2019 Beijing China (Expo 2019 Beijing) in Yanqing District of Beijing, capital of China.

Aerial photo taken on March 26, 2019 shows a pier at the site of the International Horticultural Exhibition 2019 Beijing China (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.

Aerial photo taken on March 26, 2019 shows the Guirui Theater at the site of the International Horticultural Exhibition 2019 Beijing China (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.

Aerial photo taken on March 26, 2019 shows the International Pavilion at the site of the International Horticultural Exhibition 2019 Beijing China (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.

Aerial photo taken on March 27, 2019 shows the International Pavilion at the site of the International Horticultural Exhibition 2019 Beijing China (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.