A new documentary from CGTN, Genglubu: Charting the South China Sea, delves into the story of the Genglubu—a handwritten navigation manual that guided generations of Hainan fishermen long before the advent of GPS, satellite weather forecasts, or modern navigation technology. The documentary sheds light on a little-known chapter of maritime history, revealing how fishermen from Tanmen, Hainan Province, used this manual to traverse the South China Sea, one of the world's busiest and most challenging waterways.
The Genglubu records routes, compass bearings, and sailing distances, enabling fishermen to navigate reefs, islands, and open seas. To outsiders, the manual resembles a secret code; a single line of just fourteen Chinese characters can contain an entire sea route, including the departure point, direction, destination, distance, and estimated sailing time. The documentary follows the fishermen who crossed the sea, the families who preserved this knowledge, and a maritime tradition that connected China with Southeast Asia and beyond.
Xin Lixue, curator of the China (Hainan) Museum of the South China Sea, notes, "Generation after generation, Hainan fishermen rode the waves – not to rule the sea, but to make their living from it." The documentary highlights the lives of veteran fishing boat captains like Wang Shitao, who first went to sea at age nine. At twelve, his fishing boat was caught in a typhoon; everyone else on board died, but he clung to floating timber and drifted alone for three days. Four years later, another violent storm struck, and once again he was the only survivor. Yet each time, he returned to the sea. Reflecting on decades spent sailing the South China Sea, he said, "I love the South China Sea. I hate it. I miss it."
The sea demanded sacrifice even as it provided a livelihood. As captain Wang Shubao stated, "Children and brothers should never sail on the same boat," acknowledging that a storm or mishap could wipe out an entire crew. The documentary also challenges the assumption that the Genglubu was only about the South China Sea. Research on the Liang Family Genglubu reveals routes extending to Singapore, Malacca, and Indonesia, showing that Hainan fishermen played a role in regional maritime trade. Zhao Jueqi of the China (Hainan) Museum of the South China Sea confirms, "Hainan fishermen also took part in overseas trade."
Not every route was written in words; some Genglubu manuscripts contain mountain-and-water charts combining sketches of coastlines with compass bearings, water depth, and sea conditions. These drawings helped sailors identify islands, reefs, and coastlines and determine their position at sea. International law scholar Anthony Carty notes, "The Americans and the British produced their own navigational records, which identify the Chinese as being engaged very heavily in fishing on these islands and other forms of economic activity." Today, satellites, weather stations, and lighthouses have transformed navigation across the South China Sea, but the purpose remains the same: helping sailors travel safely and return home. Genglubu: Charting the South China Sea traces a maritime tradition shaped by generations of ordinary people—a story of navigation, memory, and resilience that forms part of the shared maritime heritage of Asia.
