A map series is a group of topographic or thematic charts or maps usually having the same scale and cartographic specifications, and with each sheet appropriately identified by its publisher as belonging to the same series.
Map series occur when an area is to be covered by a map that, due to its scale, must be spread over several sheets. Nevertheless, the individual sheets of a map series can also be used quite independently, as they generally have full map surround details and legends. If a publisher produces several map series at different scales, for instance 1:25,000, 1:50,000 and 1:100,000, then these series are called scale series.
According to 2007/2/EC European directive, national mapping agencies of European Union countries must have publicly available services for searching, viewing and downloading their official map series. Maps produced by some of them are available under a free license that allows re-use, such as a Creative Commons license.
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