Tiānkōng dǎo

An area of the plane composed entirely of of completely disconnected chunks of other worlds. They float somewhat aimlessly about, occasionally colliding with each other. Just like the other areas that border the Edge, new material does get added to this region, however it tends to remain completely disconnected from the other pieces.
The largest of the "Sky Islands" is still quite small, no larger than 25 acres of horizontal area. They tend to be longer vertically than they are horizontally, so many will extend thousands of feet down. Many of them manage to support very small and thriving microclimates, but these are constantly in peril in the case of collision with another sky island.
Despite the danger and unstable nature of the place, some people do choose to live here. Many of the flighted residents of the city consider it to be an area of convenient free real estate; For others it is the ultimate place to achieve near total privacy from the rest of the citizenry, provided that you can find some method of traversing the islands.

Localized Phenomena

The maximum elevation of the islands appears to be no higher than the top of the Oathneedle, and the lowest extends down  to just above the void. Gravity still seems to apply to these islands, despite that they are floating and drifting. If you were to drop a rock off the side of one, it would plummet straight down into the void below the plane. In fact, any material smaller than 10 feet cubed or creature detached from a sky island will drop to the void below.
This effect ends when the ground of the plane becomes solid and contiguous again, and new material introduced from elsewhere in the plane will drop, even if the amount of material introduced is larger than 10 feet cubed.

Fauna & Flora

This area is absolutely infested with psedodragons, cockatrice and bats of every variety. Some of these came with edge gobbles, though it is suspected that the Cocatrice population is primarly due to escapees from a failed breeding program. 
These creatures are joined by  the occasional nest of flying snakes, stirge, or more dangerous creatures.

Alternative Name(s)

The Sky Islands, the broken lands

Type

Archipelago