Aerial photo taken on May 20, 2019 shows the scenery of Taishan Mountain in Tai'an City, east China's Shandong Province. (Photo: Xinhua)

A tourist visits Taishan Mountain in Tai'an City, east China's Shandong Province, May 20, 2019. (Photo: Xinhua)

Tourist visit Taishan Mountain in Tai'an City, east China's Shandong Province, May 21, 2019. (Photo: Xinhua)

Tourists watch sunrise on top of Taishan Mountain in Tai'an City, east China's Shandong Province, May 21, 2019. (Photo: Xinhua)

Tourist visit Taishan Mountain in Tai'an City, east China's Shandong Province, May 20, 2019. (Photo: Xinhua)

Photo taken on May 21, 2019 shows the scenery of Taishan Mountain in Tai'an City, east China's Shandong Province. (Photo: Xinhua)

Photo taken on May 21, 2019 shows the scenery of Taishan Mountain in Tai'an City, east China's Shandong Province. (Photo: Xinhua)

Aerial photo taken on May 20, 2019 shows the scenery of Taishan Mountain in Tai'an City, east China's Shandong Province. (Photo: Xinhua)

Tourist visit Taishan Mountain in Tai'an City, east China's Shandong Province, May 20, 2019. (Photo: Xinhua)

A tourist watches sunrise on Taishan Mountain in Tai'an City, east China's Shandong Province, May 21, 2019. (Photo: Xinhua)

Photo taken on May 21, 2019 shows the scenery of Taishan Mountain in Tai'an City, east China's Shandong Province. (Photo: Xinhua)

Photo taken on May 21, 2019 shows the sunrise on Taishan Mountain in Tai'an City, east China's Shandong Province. (Photo: Xinhua)