The Sentinel Plane
Controlled Realm: 100 ft Radius Around the Sentinel, Springtime. Five Hallow spells active, one in center, spell zone of truth activated, and four surrounding, with spell Obscuring Mist activated. Around the outside is a wall of earth, 500 ft tall, with a tornado force wind on the outside, to hold back monsters. There is one main gate-like area where the wall and the winds are missing. However, the gate is made out of fast renewing plant life, and holds strong. (HP 400, Regeneration 50, Fire and Negative Energy, Fast Healing 10)
Uncontrolled Realm: 100 Mile area past Controlled Realm, as Mystery Eclipse on everything, along with spell Fimbulwinter, along with Unhallow. The whole area is considered from the Frost Burn book; See book for details.
This who area is in the Material Plane, and is the spot The Deathless One punched through reality.