Once this great city was in the human realm. The castle of the great King Arthur who united the lands was here. When Arthur fell to his enemies his Penmerlin Aquila banished Camelot along with Avalon and Glastonbury to a nether realm. The intention was to keep the evil Morgen Le Fey from being able to rule the human realm.
Camelot is now colorless except the red that Morgen wears. To the soulless and damned beings who lived in Camelot, the light of Avalon was truly painful. It burned so much that only a small handful of them could bear it.