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Maps (also called playable maps, levels, or worlds) are premade environments that serve as the playable game space. Unturned has 28 maps: 10 official maps, and 18 community-created "curated" maps.
Curated maps are officially-endorsed community-created maps that have been featured in Unturned. Originally, curated maps were permanent additions added to the actual game and were treated like the official maps. Hawaii, the first curated map[1], was featured for 832 days. With the release of Bunker Arena, future curated maps would be released under the timed curated system with the notable exception of France[2]. All timed curated maps would be featured in the game for a pre-designated time, usually a month. Though originally a timed release, Canyon Arena was upgraded to a permanent status sometime post-release. Since the release of Rio de Janeiro, all curated maps have released onto the Steam Workshop rather than be added to the game files directly. New curated maps have an automatic subscription period, which commonly lasts until the next map release.
↑Though considered official, the Russia map was contributed to by the team that went on to make Hawaii, making it the first community-created "official" map.
↑France was green lit around the 3.20.6.0 update; it was made a "permanent" map to honor the original curated terms.