The so-called Nine Heavens are actually referring to the Void...
It's just a more stable region within the Void!
Above the Nine Heavens, various Great Daos reveal their glory, especially the Great Dao of Space, omnipresent like the Void itself.
But above the Nine Heavens, it is equally dangerous...
As the name implies, Nine Heavens are, in fact, divided into nine layers.
Only those who've reached the Heavenly Immortal Realm and possess an extraordinary physical body can step into the First Layer.
Above the Nine Heavens, there's hardly any Spiritual Energy, and staying for too long is extremely damaging to Cultivators.
However, above the Nine Heavens is undoubtedly the best place to comprehend the Great Dao of Space!
Even more so, there are many exotic treasures and secret realms waiting for Cultivators to explore above the Nine Heavens...