The formation and change of Qinghai Lake is a masterpiece of nature. As early as 230 million years ago, the Qinghai-Tibet Plateau was a vast ancient ocean. Two million years ago, the intense orogeny gradually uplifted this ancient ocean, forming the roof of the world. When the sea water was forced away, some of them were surrounded by surrounding mountains, forming lakes of all sizes. Qinghai Lake is a huge lake separated by mountains. At that time, it was a drainage lake, surrounded by more than 100 rivers, and the lake water flowed into the Yellow River from the east. About 6,543,800 years ago in Quaternary, Sun Moon Mountain in the east of Qinghai Lake rose strongly, blocking the exit of Qinghai Lake. The river that originally flowed eastward from Qinghai Lake was forced to flow westward into Qinghai Lake, forming a rare backward flow river from east to west in China. Qinghai Lake has also become a closed lake where running water can only enter and exit. Because Qinghai Lake is located in the northwest arid climate zone, the evaporation of lake water is greater than the injection of lake water. So the lake is falling and shrinking. Compared with the initial lake area, the lake surface has shrunk by one third, and the water level has decreased by 80- 100 m.. 1500 years ago, during the Northern Wei Dynasty, it was called a thousand miles around the lake. It was called 800 Li in the Tang Dynasty, but now it is only over 700 Li. ?

In ancient times, Qinghai Lake was called the fresh water sea, a humble and powerful sea. Tibetan is called "Cuowumbu" and Mongolian is called "Ku Counord", both of which mean blue sea.

There are many beautiful legends circulating here. ? It is said that in ancient times, the Dragon King of the East China Sea gave birth to four sons. When the sons grow up, the eldest son, the second son and the third son are the dragon kings of the South China Sea, the East China Sea and the North Sea respectively, but the youngest son has no sea to go to. One day, the old dragon king was forced to drive a cloud to Qinghai Lake. Seeing the beautiful scenery here, he gathered 108 rivers and produced the "West Sea", making his youngest son the "West Sea" dragon king.

Some people compare Qinghai Lake to "a sad tear left when the sea ebbs, or a blue memory left when the earth collapses and trembles." Whether it is "Tears" or "Blue Memories", we all regard it as a sapphire accidentally left by the goddess of mending the sky, or as a mirror embedded on the roof of the world.

Qinghai Lake used to be a freshwater lake with many creatures. After it became an inland lake, with the continuous decline of the lake, the salt in the lake gradually became thicker and the salinity reached six thousandths. In addition, due to the high altitude, the oxygen content in the water is relatively low, and plankton is scarce. Animals and plants in the lake have also been greatly reduced, and some have changed with the changes of nature. There is also a legend that Qinghai Lake has changed from a freshwater lake to a saltwater lake.

Qinghai Lake itself is a divine spring. At that time, Erlang God Yang Jian was defeated by the Monkey King and fled to this magical spring to relieve his fatigue. He used three stones to make a pot for cooking, but he took the spring water and forgot to cover it. As soon as Erlang God sprinkled salt into the pot, the spring water immediately gushed out into a Wang Yang. In desperation, he grabbed a mountain and pressed it on the sacred spring, which became the Qinghai Lake and the Haixin Mountain in the lake. The stones supporting the jar are three small islands (three stones) in the lake. The salt sprinkled in the pot is mixed with water, so the lake is salty.

Beside the beautiful Qinghai Lake, there are hardworking and kind Tibetan and Mongolian compatriots who also have their own legends about Qinghai Lake. According to Tibetan legend, a long time ago, there was only a clear spring on Senecio scandens, which was covered with slate, and the spring never overflowed. Grazing people living around must cover the slate after drinking water, otherwise it will be a disaster. One year, Lomb Gail, the prime minister of the Tubo dynasty, and his son fled here. When his son drank the water and forgot to cover the slate, the spring came out and grew bigger and bigger. Senecio scandens turned into the sea of Wang Yang, and thousands of herders were submerged by the sea. This shocked the gods, who moved the peak of the Chide Mountain in India to suppress the sea eye, thus forming Qinghai Lake and Haixin Mountain.

According to Mongolian legend, Qinghai Lake was beautiful and vast in ancient times, but the tribal leaders here bullied the people at will. There is a hero named Ku·Ku· Chun Er, who can get rid of hatred and violence and make people of all ethnic groups unite and live in harmony. After his death, he was named the God of Unity by the Emperor of Heaven to protect kindness. From then on, the Mongols called Qinghai Lake "Cuccuzzi Na".

Qinghai Lake is a beautiful and magical lake. Many myths and legends cast a thick layer of mystery on it. The most significant is the legend of Daotang River: to the west of Qinghai Lake, there is a river called Daotang River. Because most rivers in China flow from west to east, this river flows from east to west, so it is named. Legend has it that Princess Wencheng married Tubo in the Tang Dynasty and saw a vast grassland in front of her when she passed by. She changed her world. I thought she would change her sedan chair into a free ride, so she cried sadly, touched the earth and caused the river to sing, so the river flowed back to the west and accompanied the princess to the west.

By the beautiful Qinghai Lake, the splendid golden rape flowers are more beautiful because of these beautiful legends.