Tourists visit the indoor ice-snow theme park at the Harbin Ice-Snow World in Northeast China’s Heilongjiang province, June 3, 2019. [Photo/Xinhua]

Photo taken on June 3, 2019 shows the scenery of the indoor ice-snow theme park at the Harbin Ice-Snow World in Northeast China’s Heilongjiang province. [Photo/Xinhua]

Tourists play on an ice-made slide at the indoor ice-snow theme park of the Harbin Ice-Snow World in Northeast China’s Heilongjiang province, June 3, 2019. The ice-snow theme park covers an area of 5,000 square meters.[Photo/Xinhua]

Photo taken on June 3, 2019 shows the scenery of the indoor ice-snow theme park at the Harbin Ice-Snow World in Northeast China’s Heilongjiang province. [Photo/Xinhua]

Photo taken on June 3, 2019 shows the scenery of the indoor ice-snow theme park at the Harbin Ice-Snow World in Northeast China’s Heilongjiang province. [Photo/Xinhua]