

They were stacked in a conical formation to form a gigantic floating fortress a hundred floors tall. The circles were under three kilometres across at the smallest and over ten kilometres at the largest. īut one day, a hundred varied regions from around the world were cut into circles from the earth and summoned up to the sky.

While there were skirmishes at times, the land was at peace. Setting Īccording to the dark elven legends, in the long-distant past, the world was split into the forest elven kingdom Kales'Oh ( カレス・オー王国, Karesu Ō Ōkoku ?), the dark elven kingdom Lyusula ( リュースラ王国, Ryūsura Ōkoku ?), the human Alliance of the Nine ( 九連合王国, Kyū Rengo Ōkoku ?) kingdoms, the underground realm of the dwarves, and various other groupings. The vertical axis represents time and the circular floors represent space. It is also inferable that its design is symbolic for time and space. The castle's name came from the concept of a «Realized World», called An Incarnating Radius ( アン・インカーネイティング・ラディウス, An Inkāneitingu Radiusu ?), which has been abbreviated as Aincrad. It was incorporated in «ALfheim Online» on May 17, 2025. Aincrad is the world set as the stage for «Sword Art Online», declared to be the world's first VRMMORPG in history.
