The train, which runs along the Yangtze River at a speed of around 60 kilometers per hour, stops at 17 stations and takes about seven hours to reach its final destination.

Xing takes the train twice a month to commute between downtown Chongqing and the remote Wulong district.

"I prefer slow trains to bullet trains because they're cheaper and still comfortable," he said.

Of late, the regular rider has been amazed to find new bookshelves packed with hundreds of books, and desks and chairs facing the river have replaced the traditional seats in one corner of the train's No 3 carriage.

A sign reading "train library" explains the changes. "We revamped our carriage into a learning area at the beginning of the year. In the runup to the 28th World Book and Copyright Day, which fell on April 23 this year, we invited the Chongqing Library to set up its first train library aboard our train," said Deng Yeqin, head of the No 5609 train crew.

On his way to Wulong, where he and another 1,000 people are engaged in a 15-km high-speed railway construction project, Xing noticed a book written by Lin Huiyin and decided to make it his journey companion.

"I'd heard about Xu Zhimo, the famous poet who fell in love with Lin, so I wanted to know more about her," Xing said, adding that reading while traveling along the Yangtze is worth it just for the picturesque view and comfortable travel experience.

Qin Guangbin, another 50-year-old passenger, was reading documents on his laptop in the learning carriage. A businessman who shuttles between Changshou district and Xiushan, Qin has been taking the slow train for the past five years.

"I've seen great changes to this train over the years, not just the new library. I can tell how hard the crew has worked on improving the travel experience for passengers," Qin said.

As an insider who has witnessed nearly three decades of transport evolution in China, Xing has participated in construction from highways to high-speed railways, which reflects the rapid development of the country.

However, he believes that slow trains remain indispensable to the daily lives of ordinary people, as they serve farmers, students, senior citizens and other groups.

Slow trains have been working on customized services for specific groups of passengers over the years. Some have sacrificed seats to provide space for farmers who travel with livestock for sale, while Deng's train mainly ferries students, who account for the majority of its passengers, especially on the weekends.

"In the future, we will have more books and will try to enrich the travel experience for passengers," Deng added.