Tag:place=island

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Public-images-osm logo.svg place = island
Island.jpg
Description
Any piece of land that is completely surrounded by water and isolated from other significant landmasses. Show/edit corresponding data item.
Group: places
Used on these elements
may be used on nodesshould not be used on waysmay be used on areas (and multipolygon relations)should not be used on relations (except multipolygon relations)
Requires
Useful combination
See also
Status: approvedPage for proposal

An island is any piece of land that is completely surrounded by water and isolated from other significant landmasses.

How to map

Island in the sea

Draw a closed way counterclockwise along the coastline of the island (water is always on the right hand side). Then add the tags:

Island in waterway or lake

Island within lakes or rivers should be mapped using multipolygon relations.

Multipolygon representing water will have the following topology:

  1. The way for shore of lake or river (outer border of water) should have the role outer.
  2. The way for the shore of island (inner border of water) should be given the role inner.
#1 is outer, #2 is inner. Gray area represents water, empty area inside is an island. TODO: edit SVG to make it more relevant to this specific example

It's possible to create a second multipolygon representing the island with the following topology:

  • The way for the shore of island (outer border of island) should be given the role outer.

So, the same way for the shore of island will have different roles in different multipolygons.

A single closed way for the shore of the island can be used directly instead of creating a multipolygon.

If the island has a name, it can be tagged with: place=island and name=*.

You can specify the land-use, or by what it is covered with a natural=* or landuse=* tag.

Large island

Islands with coastlines having more than 2000 nodes will require a multipolygon relation to be created containing the place=island and name=* ... tags etc. See this example of the Isle of Kerrera.

When to use place=island

An island is any piece of land that is completely surrounded by water and (hydrologically) isolated from other significant landmasses;

an island is still an island (or if smaller than than 1 square kilometre tagged as place=islet ) when:

  • it is connected to the shore with bridges (not dams, that would make the island a peninsula);
  • the water surrounding the island is a river or canal
  • the distance between two shores of the mainland is filled with more land than water

For example see the Ile de Cite ("City Island") in Paris, which at its widest spans more than 2/3rd of the width between the banks of the mainland and is connected to both banks with 10 bridges, and is commonly regarded as an island (and is tagged an Islet in OSM because of the 1 km² criterium) :

Ile de la Cité, Paris, France: the width of the (combined) waters separating the island from the banks of the mainland is smaller than then the width of the island

When to avoid place=island

Small island

A small island ( Islet), with maximum area of 1 km², and only a few buildings (or none), located near a bigger island or the mainland, is drawn like a big island, but tagged with place=islet instead of place=island. Example:  Beginish

if an island is in the middle of the sea and far away of other islands, it may be tagged as "island". Example:  Wake Island

See also: Differentiation between Island and Islet (List with examples)(de).

Group of islands

If you are not mapping one island, but a group of islands, use place=archipelago instead.

Peninsula

If the piece of land you are mapping is not completely surrounded by water, use natural=peninsula instead.

Submerged sometime or all time

Consider using natural=bare_rock/rock/sand/shoal + tidal=yes, or natural=wetland + wetland=tidalflat for area that only emerge from water during low tide, and use natural=reef or subsea=* for area that always stay below water surface. was:place=island/islet might be useful in indicating features that used to be an island but is no longer an island now, so as to avoid mistagging by other contributors.

Rendering hints

If you place an island on dry land, do not expect water to automatically appear around the island.

You need to map water area.

Standard layer

Adding this tag to an island will place an italicized label on it.

The openstreetmap.org Standard layer uses a different method to render coastlines. It takes up to a day before changes to the coastline are seen in the tiles. For more details, see Coastline.

See also