Red Region = •hellfire: a place of eternal fire envisaged as punishment for the damned

Inferno = •hell: any place of pain and turmoil; "the hell of battle"; "the inferno of the engine room"; "when you're alone Christmas is the pits";
•conflagration: a very intense and uncontrolled fire
•Hell: (Christianity) the abode of Satan and the forces of evil; where sinners suffer eternal punishment; "Hurl'd headlong...To bottomless perdition, there to dwell"- John Milton

I really took the name from a poem however.
The Mid-World – by George William (“A. E.”) Russell