In the north of the Republic of Buryatia, there is a small lake, that one can walk around in about 30 minutes. The lake is called Sobolkho, which translates as "bottomless" or "flow-through."
The depth of the lake is still unknown. The temperature of the water in it never rises above 12-14 degrees Centigrade.
The lake has an ill reputation among the locals. People and animals disappear in the lake without a trace at times. There were incidents, when the bodies of those who drowned in the lake were found in other water reservoirs.
Scientists believe that Sobolkho is a natural geopathic zone, where the earth's crust has a special structure. The region of Buryatia, where the lake is located, is considered the edge of extinct volcanoes, where crust fractures are typical for the local relief.
Of course, the lake is not bottomless, but it is much deeper than other water reservoirs in the area. Scientists believe that the bottom of the lake is much larger than its visible surface. Most likely, a complicated web of solutional caves connects Sobolkho lake with other water reservoirs.
The Russian Defence Ministry harbours plans to build a deep-water submersible vehicle to reach the bottom of the Mariana Trench