The Glades had a very loose start, being spread over decades of design and changing worlds numerous times. By 'decades' ... I more mean 'millennia' in some cases, because it spans different worlds which have all had one thing in common: Etan lives on them. Whether that's because he was born there, or moved there somehow, they have him on it now, and he tends to like living in style.
On Zekira that means he steals other people's homes, moving in while the owners are away or even while they're cooking dinner, and just... making them forget about it later. He's the sort who has a collection of summer or winter homes and not one of them is his own by right. On Pern, on Alskyr, on many other worlds with or without names, Etan dominates the minds of those around him enough to just give him what he wants. Money, food, clothing, laboratory space, homes. He does spend just enough time in each of these places to decide whether the locals are worth talking to, manipulating, or just having them removed.
The current physical location of the Glades is on an earth-like world with earth-like history - it may very well even be similar to (but not exactly like) the world of Dawnlight itself, a post-apocalyptic setting that has seen its share of oddities even in the distant past of that world. It has evidence that humanity spread quickly, increased its technology level too far too fast, and fell to ruins after a vast war. It is known to have sciences and arts, but 'mad' science and 'disturbing' arts - and the exact spot where the Glades city exists is in a marsh or swamp land, rising over what appears to be an old abandoned theme park.
On Dawnlight's world (the one where Shard is from properly) this was the Disney Archology Experiment, where Walt's remains were frozen. On Zekira, the Vin Facility along with several others around the planet are kept spotless and filled with him. Even a full sized 600 unit (that's about a mall) facility has only direct clones, relatives, descendants, and a few spare non-related people that Etan trusts implicitly to do his bidding.
