‘Stranger Things’: What Is the Upside Down?

In Volume 2’s “The Bridge,” it is revealed that the Upside Down is actually part of a wormhole connecting Earth and The Abyss ...
GamesRadar+

Stranger Things season 5 cave explained: what is it, how does it connect to the Upside Down, and why is Vecna scared of it?

Supernatural Shows Where is the Mind Flayer? What is Vecna really planning with the Abyss, and 6 other questions I need answered in the Stranger Things season 5 finale Sci-Fi Shows Stranger Things ...
Yardbarker

What is The Upside Down in 'Stranger Things'? The final season will finally explain

Just what is The Upside Down in Stranger Things‘ world? The truth is that we still don’t know in full. After four seasons of the show, we know how Vecna became a part of The Upside Down and ...