Circles frequently appear within The Mists of Avalon as a physical reminder of the cyclical nature of life. Like the natural cycles within Druidic tradition, circles have no beginning and no end. They also signify the equalizing nature of life cycles: If time and life repeat, then every being has the chance to continually strive to be better. Circles often emerge in the text to signal pivotal changes to a character’s arc or the overall plot. A key example of this is when Morgaine sees the Wheel of Life, a Druid symbol, while Arthur hunts King Stag: “Higher in the sky the sun rose, the great Wheel of Life spinning in the heavens, fruitlessly speeding after her divine consort” (175). After Morgaine sees the Wheel, she completes the fertility ritual. The Wheel precedes Morgaine moving forward in her own life cycle by becoming a mother. It also represents the constant battle between the Horned One and King Stag. After killing King Stag, Arthur becomes King Stag in his place. By conceiving Mordred, he also inadvertently leads to the creation of the Horned One who will kill him.

Circles also appear when Morgaine is in North Wales seeking to recapture her priestesshood.