Did you know that the longest cave in Russia, Botovskaya, is located in the Irkutsk region? It lies in a remote area of the Zhigalovsky District, and the underground labyrinths span over 70 kilometers – and these are just the passages mapped by scientists. There are spacious galleries as well as narrow passages where one can only move by crawling. Inside, the cave is adorned with numerous stalactites and stalagmites. Stalactites hang from the ceiling, while stalagmites grow from the ground. Some stalagmites have been dated to be three million years old. In caves, the processes of formation, stasis, destruction, and reformation occur continuously, over and over again. Exploring the cave is akin to landing on another planet. Moreover, two pristine lakes were discovered here, simply named Sea and Ocean. In Botovskaya, the temperature remains constant year-round – around zero degrees Celsius. This cave in the taiga was accidentally discovered by geologists in 1946, who mentioned it in a report. However, serious studies only began in the 1990s. Scientists believe that these underground passages were known to humans as far back as 6,500 years ago. In addition to human traces, they also found dog tracks here. Tourists are prohibited from entering; only groups of researchers are allowed to descend.