More like The Fifth Galaxy Reader

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HeecheeSeries
series19 books1972
completed
Space opera, about space exploration, set in far future.
“The Heechee are an advanced alien race that visited the Solar System hundreds of millennia ago and then mysteriously disappeared.”
from the catalogue
Start with Gateway →
Known SpaceUniverse
universe142 books1964
Set in far future.
“Give a clever species a few centuries and a working fusion drive, and it will fill the sky with problems.”
from the catalogue
Start with Ringworld →
includes Ringworld, Fleet of Worlds, Man-Kzin Wars
Wine of the DreamersNovel
John D. MacDonaldstandalone novel1951
Adventurous in tone, about virtual reality.
“Wine of the Dreamers was his first science fiction novel and one of his earliest published novels altogether.”
from the catalogue
EmbassytownNovel
China Miévillestandalone novel2011
First contact, about space colonization and identity, set in far future.
“In the far future, humans have colonized a distant planet, home to the enigmatic Ariekei, sentient beings famed for a language unique in the universe, one that only a few altered human ambassadors can speak.”
from the catalogue
The Gods ThemselvesNovel
Isaac Asimovstandalone novel1972
Hard science fiction, set in far future and parallel universe.
Starship TroopersNovel
Robert A. Heinleinstandalone novel1959
Military science fiction, about war and coming of age, set in far future.