Concept art of The Convergence by Panthera Arven!
In my series/saga/thingy, there's a place called Aetheria; a seven layered realm that encompasses the two god realms (Apex/Abyss), the two afterlife locations (Beyond/Void), the two "dream" realms (Dark Depths/Sanctuary), and then the inner most section called the Convergence. The levels go as such:
Apex
Beyond
Santuary
Convergence
Dark Depths
Void
Abyss
Though spatially it's more like an interdimensional donut, where the sky of the Abyss and the Apex are the same. In other words, if you look up in the Apex you will be looking down into the Abyss, and vice versa. There's no definitive connector, so you can't tunnel up through the realms or anything, but they are all connected via portals at the center of each region.
The island in the center has a pond in the center of its crater, where you can look down into the Dark Depths (which is like a massive underground chamber of sorts). However, if you climb up the roots to the middle, you can access another portal/pond to the Sanctuary.
The middle three sections of Aetheria are the only ones to have definitive locations.
As for the Convergence itself, that pink/purple mist is known as the Misty Gates (original I know) and forms a barrier that only those of supernatural origin (deceased, gods, precursors) can pass through. A mortal will just end up coming out somewhere else along the top of the crater. The walls of the crater (as well as the slopes of the island) start tropical and warm near the shoreline but become colder and coniferous the higher you go. In the walls of the crater edge, you can find access to the Network (which is the portal connector across my universe). This means you can enter Aetheria with your mortal body, but you have to get out the same way. Which means a trip though the Farlands.
And no one wants to deal with that.
Fun Fact!
The overall feel of the Convergence is based on Crater Lake National Park in Oregon State, but is slightly scaled down with a total area of 20 sq miles.