Anharra was a Hell Dimension populated by the Anharrans Demons, a particulary wild and bloodthirsty demon warrior army.
It was originally a monarchy, etablished by the god-king Kerberon. However, when The Mistressand The Soul Glutton trapped Alexander Harris and Dawn Summers into the dimension, this last was eliminated by Dawn.
The Key became the godess-queen and instituted architecture, theater and pacifism to the Anharran demons.
It was also seen that this dimension had an Wolfram & Hart branch, under Lilah Morgan's supervision.
This world is similar to an prehistoric jungle with multiple swamps like Quor'toth. Like the Factory dimension, time moved also much faster than in Earth.