A passenger is pictured on the train No. 5640 in southwest China's Guizhou Province on Feb. 8, 2026. (Xinhua/Yang Wenbin)

For Wu Shoufen, a 42-year-old member of the Miao ethnic group in southwest China's Guizhou Province, the steady clatter of slow, green-painted trains has become a familiar backdrop to her weekly routine.

Every few days, Wu walks just a few minutes from her home in Wengdang Village to the nearby Jialao Railway Station, carrying a basket brimming with fresh vegetables. She then boards the No. 5639 train service for a 30-minute journey to Kaili City to sell her farm produce.

For Wu, this train service is more than a means of transportation; it is a lifeline connecting her remote mountain village to markets and opportunities.

Chugging through Guizhou's mountains at a leisurely pace of less than 50 kilometers per hour, the No. 5639 train and its return service, No. 5640, are anomalies in the era of high-speed rail. The 337-kilometer journey between the provincial capital of Guiyang and the Yuping Dong Autonomous County takes about seven hours, stopping at 16 stations and linking more than 100 ethnic villages along the route.

With ticket prices ranging from just 6 yuan (about 86 U.S. cents) to 44.5 yuan, the subsidized slow train service has become an indispensable part of daily life for locals.

Wu's village, Wengdang, is nestled deep in the mountains administered by Kaili City and is home to more than 2,000 residents, most of whom are Miao people. For years, isolation forced many villagers, including Wu, to seek work in larger cities. After returning home in 2012 to care for her family, Wu began using the train route to sell farm produce in downtown Kaili.

The business now brings her an annual income of about 20,000 yuan, helping her family build a new, sturdy brick house a few years ago.

"Without the trains, selling my produce would be hardly worth the effort. I'd have to walk an hour to catch a bus, and the travel costs would eat up my profits," Wu said. "On the trains, business starts early. Sometimes my sweet potatoes and corn sell out to my fellow passengers and train staff shortly after I board."

According to village official Yang Guangfen, more than 30 locals use the trains regularly to sell their goods, providing a stable income for homemakers and the elderly in Wengdang.

To better serve passengers, railway authorities have converted one carriage on each train into a display area for local produce. As people board at rural stops, baskets of vegetables and other farm produce gradually fill the carriage, creating a unique market on rail.

Hu Guichuan, 46, has worked as a conductor on the line for 29 years and has witnessed how the slow trains have become part of everyday life for those who benefit from them.

Around 2015, Hu observed that elderly farmers often struggled to sell their produce due to limited access to market information. He later created the "Green-Painted Train Supermarket" WeChat group, connecting village locals, train staff and urban buyers.

Farmers post photos of their harvests in the group, and buyers place orders online. In some cases, the trains also serve as a delivery channel, with goods loaded at one station and collected at another.

To date, the group has grown to over 140 members. Among them is Yang Guangping, who runs an agritainment business in the suburbs of Kaili and often sources ingredients directly from the trains.

"The vegetables come straight from the fields. They are incredibly fresh, and my customers love the taste," Yang said.

The rustic charm of the trains has also caught the attention of urbanites and tourists seeking a slower pace of life. Wang Xiamin, a young traveler from east China's Jiangsu Province, boarded the No. 5640 service with the intent of experiencing a nostalgic journey.

"The vendors' calls and the lively chatter in the carriage offer a glimpse into authentic local life," Wang said, adding that she had enjoyed making purchases of wild shallots and paddy fish that are rare in her hometown.

With the Spring Festival approaching, the trains have been bustling with holiday spirit. Staff have set up a temporary New Year convenience store in one carriage of each train, selling festival calligraphy couplets and holiday goods to village residents preparing for the Year of the Horse.

Despite China's high-speed railway network exceeding a total length of 50,000 kilometers, more than 80 of these humanitarian slow train services, which are subsidized by railway authorities and serve mainly remote areas, continue to operate across the country.

While fully utilizing the advantages of its high-speed rail network, China will continue to operate slow trains during the Spring Festival holiday, ensuring that people in the country's vast rural areas can visit their relatives and celebrate the Chinese New Year by train, said Li Chunlin, deputy head of the National Development and Reform Commission.