The Book of the Long Sun
Wolfe, Gene. Book series. For bibliographical details, see Wikipedia entry, as of June 2022, here.
• Nightside The Long Sun (sic). NYC, Tor, 1993. UK: New English Library, 1993. For translations and reprints, see Internet Speculative Fiction Database (ISFDb), as of June 2022, here.
• Lake of the Long Sun. NYC: Tor, 1994. For translations and reprints see ISFDb entry here. From the blog Speculiction, review of The Book of the Long Sun 8 September 2018:
Revealed on the back cover (unfortunately, I think), the setting of the Book of the Long Sun is a generation starship. Certainly not feeling that way until midway through Lake of the Long Sun, one of the joys of the book is the slow unravel of setting and the dawning comprehension just how naturalized the citizens of the Whorl (the name of the starship) are to their environment. A fresh spin on Heinlein’s Orphans of the Sky and Aldiss’s Non-Stop, everything has an Earthly feel (e.g. streets, temples, trees, lakes, bars, forests, restaurants, etc.) until more and more details begin to coalesce into the actuality of their existence. The sun a long strip of light instead of a globe, gods worshipped on television screens broadcast from Mainframe, strange and effective technology available only to the rich and well-connected, and people not always people (they may be aliens, androids, avatars, or gods in human form) [...].
The ship also has robot police; cf. and contrast THX 1138.
•Caldé of the Long Sun. London, UK: Hodder & Stoughton, 1994. For awards, translations, and reprints, see ISFDb, here. Published together with Exodus of the Long Sun as Epiphany of the Long Sun.
• Exodus from the Long Sun. London, UK: Hodder & Stoughton, 1996. NYC: Tor, 1996. See above on omnibus publication with Caldé of the Long Sun." For translations and reprints, see ISFDb here.
Writing in the early 21st century, Christopher Palmer states, "The great contemporary rendition of the Starship story is Gene Wolfe's Book of the Long Sun — but a problematic one ("Generation Starships and After: 'Never Anywhere To Go But In'?" Extrapolation 44.3 : 325).
RDE, finishing, 19Jun22