LANZHOU, Oct. 9 (Xinhua) -- Charles Coltman, an American in his 80s, shuffled across Zhongshan Bridge in Lanzhou, capital of northwest China's Gansu Province.
He paused now and then to examine its steel structure, ask about its history, and shoot videos to share with family thousands of miles away.
For more than a century, this Yellow River crossing has held a special place in the Coltman family's memory. This autumn, Coltman and his wife traveled across the ocean to see it in person.
More than 100 years ago, his great-uncle, American engineer Robert Coltman, helped build the iron bridge spanning the Yellow River.
"Everyone in the family knows about the bridge. It's something we're taught. I was taught as a young boy," Coltman said.
The story passed down through generations, mostly in family conversations. Now, more than a century later, Coltman came to Lanzhou to piece together a fuller picture of his family's history.
Invited by the provincial government's foreign affairs office, the couple visited Lanzhou from Oct. 7 to 9, retracing the family's historic ties to the city.
Today, tourists stroll across the century-old iron bridge, one of Lanzhou's best-known landmarks, snapping photos of the river and surrounding cityscape. Beneath it, traditional sheepskin rafts and modern boats ply the water.
But in the early 20th century, crossing the Yellow River was a far more daunting undertaking.
Swift currents made travel between the two banks difficult and dangerous. For generations, local residents relied on wooden boats, sheepskin rafts and floating bridges.
In 1906, the Qing government began planning a permanent iron bridge to improve river crossings.
The project went to a German trading firm and drew on American engineering expertise, with Chinese and foreign engineers and craftsmen taking part in construction.
Steel components manufactured in Germany traveled long distances to Lanzhou, where workers contended with swift currents and complex riverbed conditions. Robert Coltman was among those working alongside engineers and artisans.
Finished in 1909, the bridge greatly eased transport across the Yellow River.
For the Coltman family, though, the bridge has always meant more than an engineering feat. Charles Coltman said the family affectionately calls it "Rob's Bridge."
In 1983, Robert Coltman's youngest brother Billy and his wife traveled to China and visited the bridge, still in regular use. More than four decades on, another family member has followed in their footsteps.
One of the most meaningful moments of Coltman's visit came not on the bridge itself, but inside the Gansu Provincial Archives, where historical documents preserve details of its construction.
Among the records is a letter dated March 1908, bearing Robert Coltman's signature. Charles received a facsimile copy during his visit.
Yang Shengjun, an archives official, said the institution holds 566 documents related to the bridge's construction, eight directly tied to Robert Coltman.
The records helped fill gaps in the family story, long passed down by word of mouth. Coltman said he had known since boyhood that Robert was proud of the bridge, yet never realized how much historical material had been preserved in Lanzhou.
The archival papers were not the only surprise. Equally striking was how carefully the bridge has been conserved.
Much has changed in Lanzhou since the bridge opened in 1909. Today, more than 20 bridges span the city's 150-plus-kilometer stretch of the Yellow River, and riverside parks and scenic spots draw residents and visitors alike.
The old iron bridge, however, remains a cherished landmark. In 2004, it underwent major reinforcement and renovation, with new nighttime lighting and plazas built at its northern and southern abutments. Two years later, it was named a national major historical and cultural protected site.
In 2013, motor vehicles were permanently barred from the bridge, turning it into a pedestrian-only sightseeing span. Local authorities have kept up conservation and restoration work since, using drone inspections and sonar surveys to protect the aging structure.
Charles Coltman was particularly struck by the choice to preserve the bridge rather than replace it as the city modernized.
He said the care devoted to safeguarding the bridge's history ranked among the most impressive parts of his trip.
For local residents, the bridge is more than a transport landmark. It has witnessed the city's transformation over a century and remains embedded in the community's collective memory.
Li Jing, with the Lanzhou Yellow River Bridge Museum, said Coltman's visit adds another chapter to the bridge's story, weaving one family's memories into the broader history of the century-old landmark.
Charles Coltman left a handwritten note in a book he donated to the museum: "Thank you for keeping our memories of this wonderful achievement alive for future generations."
He plans to bring the stories and materials gathered during the trip back to the United States and share them with younger family members.
"It's a good story. I think people must remember that things happened with cooperation, (and) things happened with people from different cultures working together, and that's so important," he said. ■
