Visitors visit the Harbin Ice and Snow World in Harbin, northeast China's Heilongjiang province, Jan. 5, 2022. (Xinhua/Xie Jianfei)

A total of 100,000 cubic meters of ice blocks harvested from the Songhua River last winter have been prepared for the ongoing construction of the 25th Harbin Ice and Snow World, which is expected to open for tourists in mid-December, one week earlier than usual.

"The 100,000 cubic meters of ice blocks have set a new record for the largest ice reserve in terms of volume in our company," said Sun Zemin, a staff member from Harbin Ice and Snow World.

As man-made ice often contains air bubbles and is not strong enough to carve, ice blocks for the park are brought from the frozen Songhua River, which runs through Harbin city in Heilongjiang province. Each block of ice must be about 80 centimeters wide, 40 cm thick and 120 cm long.

It's also tradition to select and store a batch of high-quality ice blocks during the ice harvesting season for the next year's construction, he said.

Hundreds of workers will brave extremely cold temperatures and strong winds to supply the city's winter ice gala with raw materials in the following weeks.

With the help of the preserved ice, the construction has started and the park is expected to be open in mid-December, around one week ahead of schedule compared to previous years.

Using a combination of traditional ice storage and modern multilayer insulation technology, the company provided suitable storage conditions for the ice blocks — low temperature, light avoidance, insulation and sealing — ensuring the ice does not melt even when temperatures exceed 30 degrees Celsius during the peak of summer.

"To ensure the quality of the preserved ice can meet the construction requirements, we also paid a lot of attention to details such as the stacking method of ice blocks and the maintenance of moistureproof covering materials," said Sun.

As an important part of Harbin International Ice and Snow Festival, the park integrates arts, culture, performances, sports and architecture of ice and snow.

During the 24th Harbin Ice and Snow World that ran from late December 2022 to late February 2023, over 800,000 tourists visited the park, where they could appreciate 100 sets of sculptures and artwork made from more than 150,000 cubic meters of ice and snow.

They could also enjoy numerous activities, including a 500-meter ice slide, the longest built at the park to date. A giant Ferris wheel in the shape of a snowflake has been built to provide a unique experience of the dazzling world after dark.

Wang Heying, a teacher in Yangzhou, Jiangsu province, made plans to visit Harbin during her winter vacation when she got the news that the upcoming 25th Harbin Ice and Snow World will present visitors the largest scale event in its history.

"I was born in Heilongjiang's Hegang city, but my 8-year-old son never visited Heilongjiang in winter, so I decided to take him to enjoy the ice and snow as I did in my childhood," she said.