Panopticon

The Panopticon was the main room of the Capitol on Gallifrey. The Eye of Harmony was secretly kept under the Panopticon. (DW: The Deadly Assassin) The Panopticon had six sides, as that number was revered on Gallifrey. (EDA: The Ancestor Cell) When Gallifrey's suns shined on the Panopticon, the interior would shine turqouise. (EDA: The Tomorrow Windows)