From OpenStreetMap Wiki
Jump to navigation Jump to search
Public-images-osm logo.svg natural = shoal
An area of the sea floor which nears the sea surface and is exposed at low tide. Edit or translate this description.
Rendering in openstreetmap-carto
Group: Marine
Used on these elements
should not be used on nodesshould not be used on waysmay be used on areasshould not be used on relations
Useful combination
See also
Status: de factoPage for proposal

The natural=shoal tag is used to mark an area of the sea floor which nears the sea surface (literally, becomes shallow) and is exposed at low tide. This tag is used for distinct raised features like sand or gravel bars but not for tidal flats, i.e. larger flat tidal areas.

How to map


To map a shoal you can just draw a line closing on itself, marking the area area of the shoal and tag it natural=shoal. To map larger shoals you can use Relation:multipolygon with the same tag.

If known you can add the following tags:

Mapping caveats

This tag is not recommended for:

  • features that are permanently below water - instead natural=reef is recommended. However, natural=shoal is used by some mappers for sand and gravel bars that are shallow but permanently below water even at low tide.
  • features that are permanently above water - use place=island or place=islet and natural=coastline
  • for the lower part of beaches lying below the water level - these should be part of a natural=beach.
  • tidal flats, i.e. flat areas exposed at low tide but water covered at high tide - use natural=wetland + wetland=tidalflat instead.

Example rendering

Rendering-area-beach.png Rendering-area-beach-gravel.png
natural=shoal + surface=sand natural=shoal + surface=gravel

See also