(Oh boy this is the doozy: worldbuilding Alteir stuff incoming!)
The term "sky harbor" is less a place name and more of a title or official designation; there's usually one main hub for airships and sky transport in each region or sovereign nation on the most developed continents (being Avignion, Cryllt, Ciedan, New Terinth, Zolden and Sorensia - although in the case of the last one airship travel has become increasingly too perilous). So these harbors are often described with the region they are in when mentioned or are given a colloquial name that the aeronautical crew, captains and locals use instead, this one given the rather uninspired name of "Bridgeston" for its plethora of bridges spanning buildings and towers.
The phenomena of "floating earth nodes" is still not fully understood, although one universal mechanism that is exhibited by the larger ones is a strange, self-contained field that acts partly like gravity and partly like an area of stable arcane levitation. The magic that holds these floating islands aloft also "adheres" and stabilizes objects near its surface at a more or less natural orientation when in close proximity with each other, allowing Bridgeston's haphazard and precarious-looking buildings and architecture to remain more or less un-toppled. This slight, persistent magical tug also makes it fairly easy for vessels to dock safely, as long as the navigator in question is careful when making his/her approach.
Although it is impossible for it to be entirely free of servicing pirates, bootleggers and black market merchant vessels, Bridgeston is actually one of the less shady sky harbors in the North, even though its patchwork buildings and narrow winding streets make it look disreputable. It is however famous for its gambling and betting houses where even on-the-book merchants and tourists will sometimes try their hand at winning some gold on the side. Up until recent years it was also well-known for its licentious bordellos and "puff parlors" but the Triangle's ruling council and Indribel's regional sheriffs have been somewhat successful in rooting them out and keeping it that way.
I recommend a proper full-view for this one since even though it's pretty "sketchy" (I MADE A PUN) in places you can actually pick out details of the roads, bridges, buildings and archways here and there. If you look closely near the bottom you can even pick out the "warrens" carved from the stone and earth that the especially destitute or desperate live.
This didn't take me as long as one would think, but still took me long enough. Done in my sketchbook with Staedtler pigment liners over a very loose sketch. Setting specifics and the world known as Alteir are my intellectual property.