Every year on the eighteenth day of the eighth lunar month, tens of thousands of people wait at the shores of Qiantang River for an annual marvelous natural phenomenon: the world's largest tidal bore.

Qiantang River tidal bore is locally called the "Silver Dragon." The tides can reach the speed of 40 kilometers per hour and rush into the river mouth, and the water can flow up to a height of nine meters, almost as high as a three stories house.

This unique natural phenomenon is caused by the tide-generating force, which is the result of the combination of the gravitational attraction between earth, moon, and sun. 

On the eighteenth day of the eighth lunar month, our planet, the sun and moon are almost in line, so the tide-generating force reaches its maximum number. The river's horn-shaped estuary and the raising riverbed help slowing down the raising rate of the tides, the waves behind drive on those before and form a special natural phenomenon.

Watching the tidal base is a popular tourist and cultural activity for a long time. The earliest record of watching the Qiantang River tidal can be traced back to the Tang Dynasty of China. Tourists from all over the country go to the city of Haining, east China's Zhejiang Province - the best watching spot - just for a glimpse of the natural wonder. And the best watching time is near the traditional Mid-Autumn Festival, which makes Zhejiang an ideal travel spot to spend the holiday.

Facing the tidal base, a feeling of fear comes from deep inside ones heart. However, human beings always want to challenge nature, so surfing the tide is one of the most popular games during the month. People have been jumping into the powerful waves as early as the Southern Song and, at that time, they were called the Tide Players.

(Cover image is a screenshot from the video.)

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