The Hall of Prophecy consists of a pearly white antechamber and a vast and dark long room bearing a resemblance to a large warehouse or perhaps a hangar for storing a muggle aircraft. The staggeringly high shelves of the Hall of Prophecy proper form row after dimly lit row of crystal clear and somewhat bright orbs of varying sized. These small glimmering vessels hold valuable prophecies within them only attainable by the person of whom they speak. Due to it's size and the sheer volume of prophecies recorded and stored within the hall, it is not uncommon for Unspeakables stationed in this room to go for long periods through the day without seeing one another.

The antechamber is quite the opposite. Small, bright and circular, the antechamber seems to only have one door - the one which the rotating room showed you when you spoke the name of this Hall. To find the door into the Hall of Prophecy one must know where to look. Lining the walls are egg shaped pods used by those tasked with evaluating and counseling potential and established Seers.

Along with the Time Chamber and Space, this Hall forms the Unspeakable Triangle of Knowledge.