|designation = common|
|Land legally designated as common land (usually in the UK)|
|Used on these elements|
|Tools for this tag|
Common land (Wikipedia), usually just called "a common", is land over which a specific group of people (the "commoners") have certain legal rights, usually to graze livestock. Commoners usually hold this right because they live in a property which has historically had this right - the general public does not necessarily have any rights to access a common. However, as commons were necessarily unfenced (unenclosed) they were historically generally accessible, and consequently most commons are open to the public and leisure activities may be allowed.
Common land is found most often in the UK, but may also be found in other European countries.
In England and Wales
Under England and Wales law, common land must be registered with the local authority. A survey completed in 2000 lists all common land in England. Areas of land which are governed by their own Acts of Parliament, such as the New Forest and Epping Forest appear to be exempt from this registration requirement, even though they are commons.
Many commons in England and Wales, especially in urban areas, are no longer grazed and have passed into use as parks for the greater public benefit (such as Wimbledon Common and Clapham Common in London, and Midsummer Common in Cambridge). Nonetheless, they remain legally designated as common land.
The presence of the word "Common" in the name of an area doesn't necessarily mean that it is legally common land, so don't just use this tag on the basis of the name.
In more rural areas of England and Wales, much common land is still used for grazing. Commons aren't necessarily grassland - the New Forest is a common, as are many upland areas of moorland such as the Long Mynd or the Clee Hills.
Possible tagging mistakes
Until early 2019 leisure=common was rendered by the default OSM style as a green area, and was frequently mis-used across the world for general green spaces. This rendering was removed by the carto team, see discussion on GitHub.
In particular small urban areas of grass should not be tagged as commons: the most usual alternative is landuse=grass, perhaps with a further adjectival grass=* to separate this type of urban grassy area from other uses of the tag.