Qiu Qilong followed in his father's footsteps, continuing to photograph scenes from the fair every year.

In 2014, the 25th edition of the fair was upgraded to the China-Russia Expo. The same year, Qiu Guodong, 19, bid farewell to his hometown of Heihe, leaving to study at Heilongjiang Institute of Technology in Harbin.

Influenced by his father and grandfather, Qiu Guodong has been documenting China-Russia ties since he was a child. Fluent in Russian, he has a certain affection for the country.

"My father often talked to me about what the trade fair looked like, but what I saw in person was a lot different," Qiu Guodong said.

Stepping into the Harbin International Conference and Exhibition Center, where the fourth China-Russia Expo was held from June 14 to 18, left him shocked.

Cutting-edge exhibits, such as a model of China's manned deep-sea research submersible Jiaolong, an unmanned plane, nanotechnology and graphene, changed his thoughts about Sino-Russian cooperation.

It encouraged him to conduct research on cross-border e-commerce between China and Russia. "College students are encouraged to start their own business, and I think my hometown has some advantages," he said.

This year's expo also focused on further expanding common ground for the development of the Belt and Road Initiative and the Eurasian Economic Union, with merchants and government officials from 74 countries and regions participating in the event.

After another summer rain shower, Qui Xianglin once again walks along the Heilongjiang River, but there is no rainbow in sight. Instead, he raises his camera and takes a picture of a bridge being built. It will connect Heihe and Blagoveshchensk, bringing the twin cities even closer.

Xinhua