A worker takes photos at the Ice-Snow World in Harbin, capital of northeast China's Heilongjiang Province, Dec. 23, 2018. The Ice-Snow World opened on Sunday in Harbin. Covering an area of 600,000 square meters, the park used 110,000 cubic meters of ice and 120,000 cubic meters of snow this year. Over 7,000 workers joined the construction. (Xinhua/Wang Jianwei)