Reborn in the Wasteland: Pursuing the Glory of Humanity

What has happened to the once glorious human civilization? After the protagonist traveled through thousands of years, the land where brilliant culture was born has turned into a wasteland, but traces of the former glory still remain, including the airport and the broken space elevator still floating outside the atmosphere. . . The devastated land is occupied by terrifying monsters, and the remaining humans rebuild their homes just to restore their former glory. This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.