The Ithmia is the collective term used to describe three temperate forests - the Western Ithmia, Eastern Ithmia, and Northern Ithmia, divided physically by the Zaphar River and categorically by variations in plant and animal life. The term is referenced in various places, the most well-known being the former pseudonym of Hashan, called the "Crown of the Ithmia" before the catastrophe which formed the Sunderlands.
Within the Ithmia lies the city-state of Eleusis, as well as the hamlet of Bagwar's Copse, the fortress of Forest Watch, and the temple of the goddess Gaia.