Lake Baikal is a bright pearl placed by nature in Irkutsk region in southeastern Russia. Its shape is like a crescent moon, so it is also called "Moon Lake". The scenery of this lake is beautiful and unforgettable. Chekhov, a great Russian writer, once described it as follows: "The lake is clear and transparent, as if it passes through the air, everything is lifelike, and the soft green water color is pleasing to the eye ..."?

Lake Baikal is long and narrow, just like a crescent moon, so it is also called "Moon Lake". The total length is 636 kilometers, the average width is 48 kilometers, the maximum width is 9.4 kilometers, the area is 3 15000 square kilometers, the average depth is 744 meters, the deepest part is 1642 meters, and the altitude is 56 meters. Lake Baikal is clear, stable and transparent (transparency 40.8m), ranking second in the world.

Its total storage capacity is 23,600 cubic kilometers, which is equivalent to the total storage capacity of the Great Lakes in North America, covering about 1/5 of the total unfrozen fresh water resources. Suppose Lake Baikal is the only water source in the world, with enough water for 5 billion people to live for half a century. In terms of area, Lake Baikal is only the ninth largest lake in the world, but it is one of the oldest lakes in the world (with a history of 25 million years). ?

The secret of the huge area of Lake Baikal lies in the water depth, with an average water depth of 730m and a maximum water depth of 1620m. If the four tallest buildings in the world are piled in the deepest part of the lake, the TV antenna mast on the fourth building is still 58 meters below the lake. If the tall Mount Tai is placed in the deepest part of the lake, the top of the mountain is still 100 meters from the water surface.

The average temperature around Lake Baikal in winter is -38℃, which is really cold. But from June to May every year, the lake freezes and releases latent heat, which relieves the extreme cold in winter. In summer, the lake thaws, absorbing a lot of heat and reducing the heat. Therefore, some people say that Lake Baikal is a natural two-way giant "air conditioner", which can regulate the climate in the lakeside area. ?

In a year, although the ice layer of Lake Baikal is 60 cm thick for five months, sunlight can pass through the ice layer and input heat energy into the lake, forming a "greenhouse effect", which makes the lake water close to the water temperature in summer in winter, which is conducive to the reproduction of plankton and directly or indirectly provides food for other kinds of aquatic animals and promotes their development and growth. According to the underwater automatic thermometer, the water temperature at the bottom of Lake Baikal in winter is at least -4.4 1:, which is higher than the water temperature on the lake surface. Lake Baikal can adjust the continental climate on the lakeside.

At the entrance of Lake Baikal to Angara River, there is a huge stone called "Holy Stone". When the water rises, the boulder looks like it is rolling. Legend has it that a long time ago, there lived a warrior named Baikal by the lake. He had a beautiful only daughter, angara. Baikal loves his daughter very much and is extremely strict. One day, flying seagulls told angara that a young man named Yenisei was very hardworking and brave, and angara's love came from this, but Baikal flatly refused, so angara had to leave quietly while his father was asleep. Baikal suddenly woke up and couldn't catch up, so he threw a boulder, thinking that he could block his daughter's way, but her daughter had left far away and threw herself into Yenisev's arms. This boulder has been standing in the middle of the lake since then.