Avalon is the legendary home of all magic, hidden somewhere along the Web of Magic, and the central focus of the series. It and Aldenmor were both inspired by Avalon from Princess Gwenevere and the Jewel Riders.
The mages, Emily, Adriane, and Kara, were all chosen by the Fairimentals to find Avalon in order to use its supposed limitless power to restore all magic to the Web in order to save it. What the Fairimentals did not tell them was that many mages before them had all searched for Avalon and none ever succeeded, and even worse. One mage per generation would always go dark.
Such was the case when the mages prior, Lucinda, Sylvan, and Miranda, along with the help of a wizard named Henry Gardener, all created a set of power crystals to combine into one key to unlock the gates of Avalon. However, they were betrayed by Miranda, who had twisted the meaning of the prophecy and killed her own bonded, Faylinn, transforming her into the Dark Mage.
The confrontation resulted in Miranda imprisoning her sister Lucinda on the astral planes and Sylvan being transformed into a hideous half-human half-spider, and the Fairimentals stealing the power crystals so Miranda would not be able to access Avalon, leaving her with nothing but an insatiable craving for magic and power, and she would eventually become the evil half-human half-animal Dark Sorceress.
It was eventually revealed that Avalon was indeed once the home of all magic, and was remembered as an astonishingly beautiful crystal city. But long ago, when there were many human mages with bondeds, the human mages became ambitious for power as well and many of them betrayed and killed their own bondeds just to gain more power. The mages that did not waged war against these dark mages, which threatened to destroy the entire web, as well as many other repercussions and casualties, such as humans killing dragons, which forced dragons into isolating themselves in their own world, Dragon Home, as well as other magical creatures turning their backs on humans, such as mistwolves.
Eventually the war escalated to the point where all portals were sealed to prevent the mages, good or bad, from navigating across the web and bringing more destruction and it eventually calmed down, and all the human mages died out except for an astonishing few.
All this senseless violence, war, anger, hate, and greed devastated Avalon itself turning the crystal city into ruins and a place of terrible magic, thus it was locked up; the prophecy regarding three mages and Avalon itself was never a call to action but a warning.
However, by the end of the series, Miranda accessed Avalon and the mages stopped her evil forces by trapping them all in the crystal city with the method of giving up their magic to seal all portals and the Dark Sorceress was vanquished.
But this was not the end of Avalon nor its magic. Just weeks after their victory, Emily, Adriane, and Kara were astonished to learn that the magic of Avalon had moved, and the home of all magic was now Ravenswood itself. The mages were reunited with their bondeds, their friends, their jewels and magic restored, and they brought peace and magic to the entire web.
And presumably, the mages would all go to pursue relationships with certain magical boys; Emily with Prince Marlin, Adriane with Zachariah, and Kara with Prince Lorren. And of course, Ozzie presumably pursued a relationship with an elf from his old village of Farthingdale, Esmerelda when she came to Ravenswood in the form of a ferret with a bow on her head.
Avalon had two outcomes, one positive, one negative. The negative outcome was that the mages had come all that way just to unlock the doors to a place of dark magic. The good outcome was that the mages were all taught a lesson; a lesson of friendship, accepting differences, caring for everyone and protecting those you love. Avalon is the reason of the mage's friendship. ♥