Aincrad

Aincrad is the first « Realized World » shown in the Sword Art Online light novel series.

Background
Aincrad serves as the setting of the first ever VRMMORPG Sword Art Online. It has a hundred floors.

Etymology
A «Realized World» called An Incarnating Radius, abbreviated as Aincrad.

Geography
The diameter of the base floor Aincrad is about 10 kilometers, and it consists of a 100 floors stacking straight upwards. Inside, there are couple of large cities along with countless small scale towns and villages, forests and plains, and even lakes. Only one stairway linked each floor to another, and the stairways existed in dungeons where large numbers of monsters roamed. The «Teleport Gates» of every unlocked cities are connected to one another.