God of War Ragnarök features nine realms that Kratos and Atreus can visit.
The realms are drawn from Norse cosmology and include Midgard, Alfheim, Helheim, Jötunheim, Muspelheim, Niflheim, Svartalfheim, Vanaheim, and Asgard. The game expands substantially on the realm structure established in God of War (2018), where access to several locations was limited or unavailable.
Each realm has its own environments, enemies, characters, and optional activities. Vanaheim, Svartalfheim, and Asgard are especially important additions to the playable journey, while Midgard returns as a major setting affected by the Fimbulwinter.
A common mix-up is treating the nine realms as nine separate planets or as nine equally open areas. In the game, they are mythological worlds connected through travel systems and story progression, and the amount of exploration available differs between realms. The number comes from the traditional Norse cosmological framework used by the series.