100 velikikh zagadok podzemnogo mira - Lomov V.M.

The underworld is studied by experts in their field - travelers, geologists, archaeologists, cavers, paleontologists, glaciologists, volcanologists, biologists, geographers, historians, ufologists... However, less than 2% of underground cavities - caves, tunnels, craters, mostly superficial and fragmentary - have been studied. Somewhat better in terms of study is the case with man-made structures: underground temples, tunnels, dwellings, cities, water storage facilities... But until now, science cannot answer the question: how could people create these creations patiently and scrupulously, exactly ants, for hundreds of years? About a hundred great mysteries and phenomena of the underworld tells another book of the series.