The main character, a young man named Alex, discovers a hidden underground city on one of the lunar islands and learns about the history of the moon's colonization by humans. He also meets an alien race known as the Lunarians, who possess advanced technology and knowledge that could help humanity survive in a post-apocalyptic world. Book Description: На лунных островах серия «Путешествия Приключения Фантастика» (On Lunar Islands Series "Fantasy Adventures") is a science fiction novel that tells the story of a group of explorers who travel to the moon to discover new lands and resources. The main character, a young man named Alex, discovers a hidden underground city on one of the lunar islands and learns about the history of the moon's colonization by humans. He also meets an alien race known as the Lunarians, who possess advanced technology and knowledge that could help humanity survive in a post-apocalyptic world. The book takes place in a future where the Earth has been devastated by war and environmental disasters, leaving only a few scattered settlements on the planet. Humans have turned to the moon as a source of resources and a new home, but they soon realize that they are not alone on the lunar surface.

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