Russian and foreign scientists will go on an expedition where they will try to unravel the history of the deepest lake in Yakutia, Bolshoe Toko, by drilling the hole on its bottom. Bolshoe Toko is the deepest lake in Yakutia and the largest lake in Stanovoy ridge, it is also a protected natural site of republican importance. The history of its development has never been studied until now. Two other lakes were studied by the scientists of Russia and Germany in 2003, the repeated works in 10 years include the monitoring of the ecological status of the lake and the expansion of the study area. The specific feature of the researches is the deepwater drilling of bottom sediments, the analysis of which will help to discover the history of the lakes and the surrounding territory.