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The main text follows.
The Liuxi River originated in Conghua County, initially no more than a small stream. After flowing into Guangzhou Prefecture, it received water veins from east and west, and its volume surged, its surface becoming exceptionally broad. By then, calling it a stream was no longer appropriate.
As the Liuxi River passed the foot of Baiyun Mountain in Guangzhou Prefecture, its current struck an enormous reef in midstream. After prolonged scouring by the Liuxi River, the irregular, dark-gray mudstone reef gradually grew rounded, and once its outer stone skin washed away, the crimson interior was exposed, looking very much like the red coral in the Southern Sea. Thus, people called this enormous rock the Sea Pearl Stone, and called the lower reaches of the Liuxi River flowing into Guangzhou Prefecture the Pearl River.
In the narrow sense, the Pearl River ran from this Sea Pearl Stone all the way to the Lingding Ocean.
However, before the Pearl River entered the Lingding Ocean, the North River and East River joined it from either side, making it the main channel of two great rivers, while the branches of the North River and West River were themselves intertwined. Thus, this little Pearl River, originating in the Liuxi River, became the collective name for a vast network of waterways spanning Dianwen, the Miao Borderlands, the Southern Wastes, Yuyang, Three Xiang, and Yu Zhang.
To distinguish the broader Pearl River system from the Pearl River section of Guangzhou Prefecture's Liuxi River, people simply called the latter the Central River, since it lay directly between the North River and East River.
Thus, from