The Isle of the Avatar is a volcanic island, and it is still volcanically active today, in the southeast of Britannia. The island was only discovered after the end of the Quest of the Avatar and remains an unfriendly place. An attempt to build a settlement by Sir Cabirus had failed utterly, and the island was again devoid of people. Still, there is much to see on the island. To the north lies the Shrine of Humility, and in the southern half the Shrine of the Codex and the entrances to the Abyss and dungeon Hythloth can be found.
The island hadn't changed much after Ultima V with the construction of the Shrine of the Codex. However, in Ultima VII, the Fellowship had set up their camp in Hythloth, building the Black Gate there.
At the time of Ultima IX, most people believed that the Isle of the Avatar had sunk beneath the wave following the Great Cataclysm and the rise of the Columns. It was however merely a trick on the Guardian's part to make people believe this through the influence of the Columns.
This enigma of nature rose from the sea when the Codex of Ultimate Wisdom was brought up from the depths of the Great Stygian Abyss. The great subterranean upheaval that gave it birth left the large island dotted with volcanic craters, steaming fumaroles, and a ready supply of sulfurous ash. Few are brave enough to risk the hazards of this place - even to behold the Codex in the Shrine of the Avatar.
While no formal city has ever been built upon the Isle of the Avatar, it is such a place of interest that it is included here in this section. This strange volcanic island - which arose from the tumultuous upheaval of the Great Stygian Abyss - receives numerous visitors on pilgrimage to the Shrine of the Codex. The Shrine is considered to be a national monument of great historical importance to Britannia and as such is under armed guard day and night.
Birthed in the fires of righteous crusade, the Isle of the Avatar is the magical monument to the trials of the Champion of Britannia. From the Great Stygian Abyss, this isle erupted when Lord British drew the Codex of Ultimate Wisdom from the depths of the Abyss. Over the rights of the Codex, a long and protracted battle ensued between man and gargoyle. It was resolved that both shall have the right to worship the Codex on the Isle of the Avatar, a testament to the man who found peace between the peoples. Yet, during the Cataclysm, the isle disappeared. In its place on the ocean lingers a veil of fog and renewed bitterness between gargoyle and man. No ready culprit has presented himself, and much needless blood has been spilt because of it. With the woe afoot in Britannia, some claim that the righteous fires that gave birth to the Isle have faded into embers and taken it and the Codex from the people forever.