China Focus: Fishing manuals record China's early footprints in South China Sea

HAIKOU, Jan. 10 (Xinhua) -- In China's southernmost island province of Hainan, local fishing families still keep their cherished heirlooms: worn sea route manuals known as Geng Lu Bu.

For centuries, far before the invention of GPS and modern mapping technologies, local fishing families relied on these handwritten books for directions and navigation guidance in the South China Sea.

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