This version of the Arena contains no other areas besides the exterior with the Arena itself. The doors have been linked to allow you to enter/exit the arena and there are area transitions allowing access to the arena floor. In future versions, there will be other areas that cover the spaces below the arena and eventually the area outside the arena - however this release is for those who wish to create all of that themselves and just need the Arena.
The obvious one is for use in dueling, however there is great story potential here as well. The viewing area within the Arena is relatively wide which leaves room for tables at which could sit various NPC's. This Arena could also be used as the center of a great city - perhaps a starting city for a PW. Another possible use for the Arena could be to simply pit your players (as a DM) against various creatues in a contained and fitting environment.