Katherine Kerr’sDeverry Cycle creates a massive fully worked out world based on Celtic mythology over four series and fifteen books.
Not fantasy but alternative history, S M Stirling’s Emberverse books - whatever their literary merit 
- describe another fully developed universe. Lots of cultures, lots of characters, wide ranging action.
Peter F. Hamilton his Confederation Universe is spread out well with some great souls coming back from the dead stuff. Well worth a read as is his Void Trilogy.
Space Opera at it’s best!
The multiverse of the Roger Zelazny’s Chronicles of Amber are worth mentioning. And Norman’s Gor has some very well thought out analogs to various ancient Earth cultures, though the bad writing, the anti-feminist rants and the kinky sex throw many off. But it IS a well thought out world that has spawned the largest group of roleplayers in Second Life. Aaaaand outside the culture is the enormous, ancient, isolated planetary civilization of Banks’ “Against A Dark Background” which is not really part of the Culture universe.
I just wanted to throw in a micro-highjack whine about Zelazny’s Amber universe. Now, I love those books! I even love the second series, and even Betancourt’s prequels.
But… Amber is supposed to be the shining center of the greater cosmos, the glowing inspiration for all civilizations, the City of All Cities.
And what do we get? A shabby waterfront town, with a “castle” that wouldn’t pass as a damn fortification bunker in our world! Where is the vast, gleaming, intricate, ornate “Disneyfied” castle, with towers and arches and turrets? The damn thing is a pillbox, with a flat roof. No towers at all!
Zelazny could take us on glorious hellrides through landscapes beyond our imaginings…and couldn’t even conjure up a fantasy palace!
(Thank goodness for fantasy artists who transcend the written description and paint a picture of Castle Amber the way it bloomin’ ought to be!)
Further ranter saith not.
Sometimes reality bites. You don’t get much realer than Amber herself. She’s the one that defines what’s real, after all. Corwyn would tell you, if he were here, that Oberon wasn’t terribly interested in airy-fairy flights of fancy…that’s what he broke away from over in Chaos, after all. No, sober practicality and anti-Chaos security prevail. You want towers, head for Shadow.
I give a strong and hearty recommendation to Jack Vance’s Lyonesse trilogy. It probably doesn’t have the absolute largest number of characters and subplots and locations, but it is a marvelous piece of writing in every respect.
Delightful insight! So you might say, as one nears Amber, the towers get more fanciful, but when you actually arrive there, you see blunt, concrete, functional reality?
Agreement! Fun, well-developed, deep, complex, and a joy! The scenes in Thripsy Sidhe are otherworldly and magical; the worldly and material scenes range from light and fanciful to blunt and brutal. Vance had an enormous range on dramatic tonalities.
Just from reading the “race to the throne” sequence, my heart was pounding as if I were sprinting to a finish line.
In the same way, the “Oikumene” of his “Demon Prince” novels (which he revisited, a little, in some later and, alas, lesser sf) is a most detailed and wonderfully realized spacefaring civilization. He performs wonders in justifying the apparent contradictions in tech levels, because, although his universe has futuristic super high tech…it also has a very active “Institute” – a kind of organized Luddite society – striving to keep the tech suppressed. This, and so many other details, make the world come to life!
(And if that weren’t enough Jack Vance, the four novels of the “Tschai, World of Adventure” novels are also an exploration of an immensely detailed world, where anything can happen…and usually does! He throws in four or more alien races, a burgeoning human sub-population, ancient ruins and secret tunnels, spaceships, manhunts, and more adventure than anyone could ever hope for! This series is sort of a hybrid between Barsoom and “serious” science fiction.)
I read the “Night’s Dawn” trilogy. Doorstoppers each. It’s been years and this story has stayed in my head a lot more than most of what I’ve read. The realistic space flight dealing with acceleration and gravity was refreshing.
You mean “Eddings”. Unless you are talking about a spinoff using the Moonlighting characters.
We’re only two books in, but Sanderson’s Stormlight Archive books give every indication that the series will be epic.
A friend of mine is a fantasy artist; here’s her conception of Amber
They never went into umpteen books but the “Deathworld” series by Harry Harrison and a lot of his other series are pretty good.
Okay, I’ll bite. How is a Dyson Sphere too big? So what if it takes a million years to populate fully? Or did you mean too massive? I can imagine a Dyson Sphere being problematic in the case of a close stellar encounter.
The Saga of Recluce series by L. E. Modesitt, Jr. is pretty damn good. There is a chronology to the series, but the books jump around in it if you read them in publication order. The first book in the series is The Magic of Recluse. However, the first book chronologically is book 6, Fall of Angels.
However, they are all standalone. Modesitt tells a good story in each one of them, period.
That’s BREATHTAKING! Fantastic, and just endless! It makes me think a little of Breughel’s “Tower of Babel,” and it also has some Escher-like infinities to it. The swirling of Tir-na Nog’th in the sky is wonderful. The more I look at this picture, the more I see! I love the archway in the lower center, and, just below it and to the right, the subtle climbing arcade/façade. And now I see the people on the balconies at the very bottom! Please pass along my absolute dumbstruck and awestruck admiration for this piece! (Are prints available?) Delicious! I want to go and visit and never leave!
CalMeacham mentioned they were “civilization killers.” I think the concept is that if you have an unlimited frontier, it will attract “frontiersmen,” and while some of them are civilization-builders, others are discontented and disaffected sociopaths. Thus, there will always be an expanding cloud of nihilism/barbarism/anarchy – or just poverty and ignorance – flying ahead of the enclaves of civilization that people strive to build. Organized infrastructure would always lag behind, to the ultimate degree of civilization’s collapse.
The concept of a single “Earth Government” is possible. (No matter what you might think of it, it could happen.) But a single Dyson Sphere Government is (so some have claimed) absolutely impossible.
(I’d disagree, on the grounds that sufficiently advanced computer technology – not even AI, but just hyper-advanced administrative tools – might be able to govern an unlimited area and population.)
But eventually the Dyson Sphere will fill, and if you let the population explode, it will fill very quickly indeed - in perhaps as little as a few thousand years.
I too disagree. Just because current bureaucratic structures won’t scale to that level doesn’t mean that we can’t invent new ones that do.
Not so different, actually.
Six books that I’ve read so far. Two that deal with Valentine, one that’s a collection of short stories, and three that deal with Prestimion. A quick check of Wiki reveals a couple of novellas and another novel I haven’t read.
Also from Silverberg, Roma Eterna is an interesting big idea best described as “What if the Roman Empire never fell?” that is very much your mileage may vary.
Allen Steele’s Coyote series got big pretty quickly, although the first couple of books are collections of material originally published in Asimov’s.
Again, big ideas (if somewhat limited in characters) are in Charles Stross’ Accelerando, which again is a collection of previously-published material from Asimov’s. I’ve heard good things about his Merchant Princes series as well but I haven’t read them.
According to the internets, if you’re interested in Big Dumb Objects (not a pejorative), you can also look at reading:
Niven’s Rainbow Mars
Ian M Banks’ The Culture series
Robert Reed’s Great Ship
And I’m sure there’s a lot more, those were just the first three that stuck out to me on TV Tropes.
