The place where Allissa found the baby Dragon Jayden
a Dream Stone -lined shaft which D'zeron children climb down to practice their climbing skills. at the bottom of the well is a cave [also made by the Ancients and lined with Dream Stone ] which is called the Cave of Silence.
in Allissa's time the original purpose of this artifact has been forgotten by the people of D'zeron but not by the Ancients.
the well/cave is designed to be a place where the Dream Plane cannot enter[sort of the opposite of the Temple , which is designed to invite the dream plane, sort of like the Pillars which are designed to protect the village somewhat from the influence of the dream plane.
Jayden was placed in the cave by Lenn in order to get Montarra to consider him dead/gone so she would ahtch out another egg, Aubyn which Lenn had formed a dream bond with before it hatched and wanted to hatch at that time. Len intended to go back and rescue Jayden before he dies due to the dream plane seperation which is very harmful to dragons. Allissa got to him first, saving his life and thus incuring in him a debt and thus a bond until the debt was paid. by later saving Allissa from Montarra Jayden pays the debt releases himself from obligation to Allisssa and goes home. Allissa then goes on to meet Lenn and Aubyn in the Ancient Forest .
the well becomes important again when Lenn, knowing hat it is, sends her and Chathalen there to overcome the barrier. they can safely interact there where the dreams cannot come, and then through a revelation they have involving a Christlike figure appearing in a fire they realize they need to climb out of the well together face the barrier and refuse to be destroyed by it. they do this and it takes them back to the time the barrier is formed and they replay the scene ending with Allissa choosing to love him and stay with him rather than casting the barrier.
ironically perhaps Chathalen goes on to use the same sort of barrier to save Harris and become Dream Bound and then commands Allissa to marry Harris Jenzar .