When Japanese director Ryo Takeuchi appeared for his scheduled online interview with China Daily, he was sitting in a cafe near a historical site in Zhengzhou in Henan province.

"Look over here, the ancient wall behind me dates back 3,600 years," he said enthusiastically via his phone, pointing out of the window, before revealing that he planned to visit the Yellow River Museum the following day.

From May to June, Takeuchi traveled across the country to promote his documentary The Yangtze River, an acclaimed feature which has received a rating of 8.5 points out of 10 on the popular review aggregator Douban.

Moved by scenes that vividly reflect life along the titular river, viewers in cities along other rivers in the country also invited him to consider making their rivers the subjects of his next projects.

"In northern China, people expressed their desire for me to shoot a documentary about the Yellow River. When I visited cinemas in southern cities like Guangzhou and Shenzhen, people recommended that I make a documentary about the Pearl River," says Takeuchi.

In Zhengzhou to attend a cultural activity, Takeuchi explained why he had seized the opportunity to explore the history and culture of the city, a historically significant location along the Yellow River.