On the Yellow River at Hunan is a waterfall called the Dragon Gate. It is said that if certain carp called Yulong can climb the cataract they will transform into dragons. Every year in the third month of spring they swim up from the sea and gather in vast numbers in the pool at the foot of the falls. It used to be said that only seventy one could make the climb in any year. When the first succeeded, then the rains would begin to fall. This Dragon Gate was said to have been created after the Flood by the god-emperor Yu who split a mountain blocking the path of the Yellow River. It was so famous that throughout China there was a common saying that: 'a student facing his examinations is like a carp attempting to leap the Dragon Gate.'
Hunan is not the only place where this happens. Many other waterfalls in China also have the name Dragon Gate and much the same is said about them. Other famous Dragon Gates are on the Wei River where it passes through the Lung Sheu Mountains and at Tsin in Shanxi Province.