Aerial photo taken on Feb 22, 2019 shows tourists visiting the West Lake by boat in Hangzhou, East China's Zhejiang province. [Photo/Xinhua]

Aerial photo taken on Feb 22, 2019 shows tourists visiting the West Lake by boat in Hangzhou, East China's Zhejiang province. [Photo/Xinhua]

Aerial photo taken on Feb 22, 2019 shows tourists visiting the West Lake in Hangzhou, East China's Zhejiang province. [Photo/Xinhua]

Aerial photo taken on Feb 22, 2019 shows tourists visiting the West Lake in Hangzhou, East China's Zhejiang province. [Photo/Xinhua]

Aerial photo taken on Feb 22, 2019 shows tourists visiting the West Lake in Hangzhou, East China's Zhejiang province. [Photo/Xinhua]

Aerial photo taken on Feb 22, 2019 shows tourists visiting the Guozhuang scenic area by the West Lake in Hangzhou, East China's Zhejiang province. [Photo/Xinhua]