Place of Awakening - Abyss Preview Dungeon?
When you first Awakened in the [Tutorial Dungeon], there were some inaccessible locations blocked by rubble. Shortly into the game, you will learn how to use your Right Hand of Reversal powers to clear rubble that will allow you to access that area in floor B1F "Pit" of the Beginning Abyss. After clearing two piles of rubble, you will reach a deactivated teleporter. From B1F, there is currently nothing else you can do here.
However, when you later learn to use the Cursed Wheel, you can leap back in time to Awakening, reliving the opening scenes of meeting Lulunarde (and giving you the chance to change the main character's Name) and exiting the Place of Awakening, which looks suspiciously identical to B1F. Now you have the ability to reverse the piles of rubble, and only immediately after Awakening is that portal active.
Place of Awakening map
It seems to make no difference if you do it before or after meeting Lulunare, but stepping into that portal will teleport you to a new dungeon, with more rubble to reverse. This new dungeon has the enigmatic name "???".
???
There's not much here, other than a preview of the dungeon style of the Beginning Abyss and a few more rubble piles to reverse. In one of the rooms after some of the rubble is another teleporting, taking you to ... another "dungeon" floor that looks strangely like a flooded city. This time it has a name: "Cave of Water".
Cave of Water
This time, you're ability to explore is limited by a strong current of water coming from a serpent-shaped statue. As anyone can tell you who has progressed to the second Abyss, Trade Waterways dungeon in Port Town, this dungeon is giving a previewing of that Abyss style, and you can only navigate your way to another teleporter that takes you to... another dungeon. This one is named "", and unsurprisingly is a preview dungeon for Abyss 3, the Impregnable Fortress in Guarda called _.
To Be Continued ...