OpenStreetMap: edit the free map of the world with the community
OpenStreetMap is a free map of the world built by a growing community of mappers who contribute and maintain data about roads, trails, cafes, railway stations and much more all over the world, using local knowledge, aerial imagery and GPS devices. Anyone can edit the map, and step-by-step guides for beginners are collected on LearnOSM. Age and deadline are not stated on the page, and participation is ongoing.
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