This name refers to the areas of the First Tower of Ar tonelico that are located below the Terraced Fields, and are separated from the upper floors by a barrier wall, made to keep the poisonous gas from the Sea of Death from going up. Not much is known about these areas, given that no one has visited them in the last 700 years. However, Shurelia is still able to sense anything that happens down here, and can somewhat monitor the systems in case anything happens.