Key:ele

+/- ele Description Elevation of a point in metres in WGS84. Group Ele Element help Useful combination Key:name Key:operator Used combinations in World Australia/Oceania Europe (list) Asia (list) Central America (list) South America (list) Africa (list)

→ see Altitude for more specific description

Elevation (height above sea level) of a point in metres. This is mainly intended for mountain peaks but could also be used for elevation of airport runways and many other objects. For OpenStreetMap, please use the elevation above sea level defined by the World Geodetic System, revision WGS 84.

In the case of buildings and other man_made structures that stand on the ground, use the elevation of the surrounding ground, not of the structure itself (e.g. don't tag the roof top or the tip of a tower, but tag the ground level and add the height with the tag height=*).

Basics

OSM currently records points with their latitude and longitude (x/y coordinates), elevations are recorded less frequently. Where this is done, the elevation in WGS84 is stored in the ele=* key.

A proposal for map datums other than WGS84 is to store them in keys such as ele:xyz=####.##, where xyz is the map datum and elevation is specified in meters.

Another source of elevation data is SRTM. It can be superimposed on the base map as a transparent layer, as OpenCycleMap and Reit- und Wanderkarte do. However, SRTM considers only elevation differences above 50 m; furthermore, it does not represent the terrain but the highest points (which may be trees or high buildings). It is not connected to OSM data, hence e.g. inclinations cannot be obtained from it without further processing.

National reference systems

Elevations posted on official signs are usually relative to the national reference system of the respective country and have to be converted to WGS84.

Country	Standard	Common name	Heights	Tide gauge	Reference point	Conversion
Australia	Australian Height Datum	Metres above mean sea level		32 distinct tidal references points on Australian coastline.	Ausgeoid09.	Conversion calculator online
Austria		Meter über Adria (m ü. Adria) (meters above Adriatic)	Normal-orthometric	Trieste 1875	Hutbiegl
Belgium		meter boven Oostends Peil (m O.P.) (meters above Oostende tide gauge)	Orthometric	Ostende	Ostende
Czech Republic		metrů nad mořem (m n.m.) (meters above sea level)	Normal	Kronštadt
Finland			Orthometric	Helsinki	Helsinki
France (mainland)	NGF-IGN69	mètres au-dessus du niveau de la mer (m) (meters above sea level)	Normal	Marseille	Marseille	[1]
France (Corsica)	NGF-IGN78	mètres au-dessus du niveau de la mer (m) (meters above sea level)	Normal	Ajaccio	Ajaccio	[2]
Germany *)[1]	DHHN92	Meter über Normalhöhennull (m ü. NHN)	Normal	Amsterdam	Wallenhorst
Former West Germany *)	DHHN12	Meter über Normalnull	Normal-orthometric	Amsterdam	Hoppegarten (near Müncheberg)
Former East Germany *)	SNN76	Meter über Höhennull (m ü. HN)	Normal	Kronštadt	Hoppegarten (near Müncheberg)
Hungary		Tengerszint feletti magasság	Normal	Kronštadt	Nadap
Ireland		meters above sea level (m ASL / m a.s.l.)	Orthometric	Maln Head	Maln Head
Italy		metri sul livello del mare (m s.l.m.) (meters above sea level)	Orthometric	Genoa	Genoa
Japan **)		Tōkyō-wan heikin kaimen (東京湾平均海面) (Tokyo Peil, T.P.)	Orthometric	Chiyoda, Tokyo	Nihon suijin genten (日本水準原点), 24,4140 m **)
Liechtenstein	LN02	Meter über Meer (m ü. M.) (meters above sea level)		Marseille	Geneva
Luxemburg			Orthometric	Amsterdam	Amsterdam
Netherlands		meter boven/onder NAP (m NAP) (meters above/under NAP)	Orthometric	Amsterdam	Amsterdam
Norway		meter over havet (moh.) (meters above sea level)	Normal-orthometric	Tregde	Tregde
Poland		metry nad poziomem morza (m n.p.m.)	Normal	Kronštadt
Portugal		Nível Médio das Águas do Mar	Orthometric	Cascais	Cascais
Russia		vysota (metry) nad urovnem morja (высота (метры) над уровнем моря) (elevation/meters above sea level)	Normal	Kronštadt	Kronštadt
Slovakia		metrov nad morom (m n.m.) (meters above sea level)	Normal	Kronštadt
Slovenia			Normal-orthometric	Trieste 1900	Ruse
Spain		metros sobre el nivel del mar (msnm) (meters above sea level)	Orthometric	Alicante	Alicante
Sweden		Meter över havet (m ö.h.) (meters above sea level)	Normalhöhe	Amsterdam
Switzerland ***) [2]	LN02	Meter über Meer (m ü. M.) (meters above sea level)		Marseille	Geneva
Turkey			Normal-orthometric	Antalya	Antalya
UK		meters above sea level (m ASL / m a.s.l.)	Orthometric	Newlyn	Newlyn
Former Yugoslavia		Nadmorska visina (m/nv, ~meters above Adriatic)	Normal-orthometric	Trieste 1875/1900

*) DHHN92 was adopted gradually after reunification. Even newer topograpic maps may still use the former reference systems.
Former East Germany used DHHN-12 on the territory of East Berlin, in rail contexts and for landlocked waterbodies.

**) National authorities use this datum only for the four main islands of Hokkaidō, Honshū, Shikoku, Kyūshū and associated islands. For Sado, Oki, Tsushima, as well as for the Izu, Ogasawara and Ryūkyū islands, the mean sea level of a nearby coast or bay is used. For example, the reference point for Miyake-jima, which belongs to the Izu islands, is the mean sea level of Ako Bay on the western coast of the island.

***) LN02 remains in force. For LHN95, which uses orthometric elevations, the reference altitude of Repère Pierre du Niton was kept. ^[3]

Example

The height of Breithorn in Switzerland is 4,164 metres. It could be mapped as:

natural=peak

name=Breithorn

ele=4164

The height of rail tracks in Tanggula railway station is 5,068 meters. It could be mapped as:

railway=station

name=唐古拉

name:bo=གདང་ལ་།

name:en=Tanggula

name:zh=唐古拉

ele=5068

See also

• layer=* - used to mark layering of map elements
• height=* - used to mark how tall a map object is
• alt=* - Proposal to mark exact altitudes concerning to the reference system of heights. Deprecated.

References

1. ↑ Bundesamt für Kartographie und Geodäsie (BKG):Höhenreferenzsysteme in Deutschland.
2. ↑ http://www.swisstopo.admin.ch/internet/swisstopo/de/home/topics/survey/networks/ln02.html
3. ↑ http://www.swisstopo.admin.ch/internet/swisstopo/en/home/topics/survey/networks/lhn95.html