Why is flat tide called flat tide?

1·The origin of the place name "Pingchao"

Pingchao was called Shanjiadian in ancient times, also known as Taocun. Because it is thirty miles away from Tongzhou City, it is also called "Thirty Miles" .

In the Renwu year of Emperor Qianlong of the Qing Dynasty (AD 1762), Emperor Qianlong went to the south of the Yangtze River by waterway. It rained continuously for several days. When passing through Tongzhou, the weather began to clear up. Emperor Qianlong stood on the bow of the boat and wrote a poem about it. One song: "The vast waves of the river wash away the sand, stirring up the turbidity and clarifying it before the tide calms down.". After that, the emperor gave it the name "Pingchao". (Source: Tongzhou County Chronicle)

2. Pingbei, Pingnan and Pingxi are all flat tides.

3·Introduction to Pingchao

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