Plutonia

Originally published in 1924, "Plutonia" is a hollow-earth-type of science fiction novel set in an underground world of rivers, lakes, volcanoes, and strange vegetation, a world which has its own sun -Pluto- and inhabited by monstrous animals and primitive people. The author uses the plot for the purpose of introducing the reader to the animal and plant life of ancient geological periods in their natural surroundings.

Academician Vladimir Obruchev was an outstanding Soviet geologist and geographer, a famous explorer and investigator of Central Asia and Siberia, an indefatigable popularizer of scientific knowledge, who wrote thousands of scientific articles and a total of three science fiction novels, including this one.