Since its construction, the complex has hosted the coronation of successive kings of Nepal, as well as celebrations and religious activities.

"Combining Hindu beliefs with the essence of traditional Nepalese architecture, it embodies Nepal's historical processes and national memories, encapsulating rich cultural traditions and high artistic achievements," Liu said.

After the cultural heritage was destroyed, the Chinese and Nepali governments agreed to launch a restoration project of the Basantapur Tower complex.

It was the first large-scale cultural heritage aid project that the Chinese government carried out in Nepal.

Under the guidance of the National Cultural Heritage Administration of China, the Hebei Institute of Cultural Heritage and Ancient Architecture Preservation took on the mission of survey and design for the project, as well as supervision and management during the restoration, while the China Academy of Cultural Heritage undertook the actual restoration work.

In December 2016, the Hebei institute organized a special team for this project, with Sun mainly responsible for the survey and design work.

The team completed the restoration plan in April 2017, guided by other professionals. The plan was then approved by Nepal's Department of Archaeology.

"The China Academy of Cultural Heritage undoubtedly represents our national team in the field of ancient architecture restoration, showcasing the highest level, while the team from Hebei also stood out in the field," Liu said.

According to Liu, over the years, the Hebei institute has been involved in some major cultural heritage conservation and maintenance projects such as the restoration of the Sakya Monastery in Xizang autonomous region, and the mountain resort and surrounding temples in Chengde, Hebei.

"Our teams also participated in significant post-earthquake projects, including the ancient building conservation and maintenance in Wenchuan, Sichuan province. We have accumulated rich experience in the restoration of cultural relics and ancient buildings," Liu said.

"For the Nepal project, our design team had to overcome various difficulties and completed the on-site survey and design proposal on schedule," Sun said.