Wikipedia:Obtaining geographic coordinates

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There are various ways to obtain geographic coordinates. Note that regardless of the source of coordinates, it is a good practice to evaluate whether they appear reasonable at first glance.

Manually[edit]

  • Using a GPS receiver with a clear view of the sky.
  • Looking at a printed map or atlas, either those you own or at a library.

Public domain databases[edit]

On the web[edit]

Wikipedia compatible geotagging metadata generators[edit]

List of services, directly providing Wikipedia/Wikimedia Commons compatible geotagging metadata.

Currently preferred geotagging templates are: {{coord...}} for English Wikipedia and {{location...}} or {{location dec..}} for Wikimedia Commons.

Tool Type Metadata types Coordinate parameters Description Licensing
GeoLocator
(project page)
Google Maps based {{coord}}, {{location}}, {{location dec}}, microformats, custom editable template type, scale, region, heading Coordinate picker and online metadata authoring tool.
Features: visual heading (camera direction) picker, GeoTemplate/GeoHack compatibility, flexible coordinate parser, URL integration, configurable degree/arcsec precision. Metadata roundtrip support – pasting of existing geotag, updating its location or parameters and encoding new one.

Generic web based services[edit]

These services are web based, and provide on-line methods for obtaining co-ordinates.

Be sure to read the licensing information carefully so that data providers receive an appropriate attribution.

Tool Type Description Licensing
GISWiki Google Maps tool The hjl_get_Coor tool has been developed, which takes the coordinates from a Google Map and builds the {{coord...}} or <geo>...</geo> markup.
There is a version for the English Wikipedia available.
?
EarthTools Global browser Designed to give coordinates for places, sunrise and sunset times, local time zones elevation/height above sea level. It's extremely easy to use and has a very nice interface (takes Google Maps and adds more functions to it). ?
3maps Maps Allows you to paste the URL from many popular online mapping tools and get the current place and coordinates. Can search coordinates from a raw paragraph of text. The smart address search. ?
NASA World Wind NASA World Wind Open source 3D interactive world viewer. See also: Spoon.net for online version NOSA
Bing Maps Maps Provides geographical coordinates of a location when a "Pushpin" has been created.
  1. Find the feature or the location you want to know the geographical coordinates of, either by manually using the map and zooming in, or by entering a place name or address into the search field.
  2. Right-click on the map at the site where you want the pushpin to appear.
  3. A pop-up tab will appear. Select Add a Pushpin and save it.
  4. Several icons are found to the lower left of the map, including a star for "My Places" and also an email icon. Click the Star to open "My Places".
  5. Select the most recent place which you have just saved.
  6. Click the email icon. The geographical coordinates are embedded in the email link which is then displayed. The coordinates are the two numbers displayed immediately after the letters "cp=". The latitude and longitude are separated by a tilde ( ~ ). The latitude is displayed first, and both coordinates are displayed in decimal degrees format. (in degrees only).
  • Alternatively, any of the locations in My Places can be exported either as a KML file or GPX file, both of which embed the coordinates. Export is done by clicking the Actions tab at the top of the My Places box.
  • The degrees-only geographical coordinates can be entered into Wikipedia's {{coord}} template. In the preview, click on the template and you will get to the Map sources page. There, the degrees-only geographical coordinates are converted into degrees-minutes-seconds anyway and displayed automatically at the top of the page, so you can still decide if you want to convert the degrees-only-geographical coordinates into the degree-minutes-seconds-format (alternatively, you can also use the website http://id.mind.net/~zona/mmts/trigonometryRealms/degMinSec/degMinSec.htm for the conversion from degrees-only into degree-minutes-seconds).
Proprietary EULA
WikiMapia Global browser The latitude and longitude of the crosshairs are given at the bottom left of the screen and are constantly updated as the map is moved. Clicking on them will bring up a dialog box from which they can be copied in decimal or deg/min/sec form. Arieal imagery provided is from Google Earth Terms of use
Calculators Conversion Many scientific calculators (including the one that comes with Windows, use dms and inv dms) can convert coordinates.
The Getty Thesaurus of Geographic Names Name search Allows you to find coordinates with a place name search. [1]
World Gazetteer Name search Provides geographic coordinates of many cities (select country – "cities" – city) [2]
Geonet Names Server (GNS) Name search U.S. National Geospatial-Intelligence Agency (NGA) maintains a comprehensive database of non-U.S. place data.
The Libre Map Project The purpose of the project is to aggregate and make digital maps and related GIS data available for free. CC-BY-SA 2.0
Microsoft Research Maps Global browser Free online repository of public domain aerial imagery and topographic maps provided by the U.S. Geological Survey (USGS).
GPSies.com Google Maps tool Gives coordinates for places, names, elevation/height above sea level on Google Maps (reverse geocoding). You can download the coordinate as GPX Waypoint, PCX5 Waypoint, LOC Geocache or Google Earth KML.
GeocodeFarm Address & coordinate search Look up address by coordinates or coordinates by address. Forward and Reverse Geocoding Service. Web Form or API Available. API is free for 2,500 queries per day, more are paid. Web Form is free for unlimited queries. International Coverage in most countries. [3]
Geocoder.us Address search Look up the coordinates of any location in the United States by its address or nearby intersection. Only works for US addresses. [4]
Great Circle Mapper Name search Has geographic coordinates for airports, heliports, and other facilities which have an IATA or ICAO code. You can also search by location name.
JRC Fuzzy Gazetteer Fuzzy name search Spelling tolerant place name gazetteer, mostly based on GSN data, enriched with data collected from United Nations missions and European Commission services.
Plexscape WS Google Maps tool – Coordinate converter Online application to acquire coordinates for any place on Earth.
  • Supports more than 3,000 coordinate systems and 400 datums worldwide.
  • Place pushpins on the map and calculates automatically the coordinates in the selected coordinate system or datum.
  • Perform transformation between coordinate systems and/or datums.
  • Extended units list available for calculations (meters, feet etc.)

Coordinates also can be found in other sources, such as:

Google tools[edit]

  • Google Maps can be used to find coordinates 3 different ways, although many other sites make use of Google imagery with specialist overlays.
    • The simplest way to get coordinates from Google Maps is to right-click on the desired location and click "What's here?". The coordinates are now shown in the search box.
    • Another method is using the LatLng ToolTip from Google Maps. This feature is activated through Google Labs by entering its Google Maps Labs section here. The Tool Tip will display a box with coordinates that move as the mouse cursor is moved. Note that the upper left corner of the tooltip box actually becomes the precise point of the cursor whose coordinates are displayed in the box. There is also a related LatLng Marker tool which is useful because it makes it easy to copy and paste the coordinates.
    • Coordinates can also be extracted from generated links with the following procedure. First locate the place you require coordinates for, and double click on it to centre the map around that point. Then click "Link" at the top of the map, and the coordinates (in degrees and parts of a degree in decimals) appear in the address bar, e.g. "http://maps.google.co.uk/?ll=51.455558,-2.605047&spn=0.032304,0.069523". In this case the latitude is 51.455558, and the longitude is -2.605047. The reverse is possible by entering the lat and long into the search bar, with a space between them. Based on Google Maps API and geocoder, this page simplifies the task by displaying directly the coordinates, including in one of Wikipedia formats (for English and French Wikipedias), and allowing quick finding of places either by moving the map or typing in postal addresses or place names. Informal research indicates that coordinates obtained in this way usually agree with precisely determined WGS84 coordinates to within about ten meters, or four decimal places in decimal degree notation.
    • Copying the coordinates from the URL can be made easier with a Javascript-supporting browser, by adding the following bookmarklet (create a new bookmark with this code as the URL):

      javascript:void(prompt('',"{{coord|" + gApplication.getMap().getCenter().lat() + "|" + gApplication.getMap().getCenter().lng() + "}}"));

      Centre the map on the point as previously, and then open the newly created bookmark. A coordinate template text will appear, ready to be pasted to Wikipedia. Alternatively, to format the coordinates directly into the template code for articles, with display next to the title, use the following code as a bookmarklet:
Caution: a previous version of this code was faulty. If you installed this Bookmarklet before June 15. 2009 please update it with the current version..

javascript:coord=[gApplication.getMap().getCenter().lat(),gApplication.getMap().getCenter().lng()];output='{{coord|';for(x in [0,1]){neg=(coord[x]<0);coord[x]=Math.abs(coord[x]);deg=Math.floor(coord[x]);minr=(coord[x]-deg)*60;min=Math.floor(minr);sec=Math.floor((minr - min)*60*100000)/100000;output+=deg+"|"+(min<10?'0':'')+min+"|"+(sec<10?'0':'')+sec.toFixed(2)+'|'+(x==0?(neg?'S|':'N|'):(neg?'W|':'E|')+"display=title}}");};void(prompt('Coordinates for Wikipedia',output));

  • Googling for the city name together with "latitude", "longitude", which will give hits like http://www.infoplease.com/ipa/A0001769.html
  • Google Earth makes it easy to search for the coordinates of any location and zooming in on them. There are many ways to obtain coordinates:
    • Move the mouse cursor to where you want, and note the coordinates displayed in the lower left-hand corner of the earth display window. The display format can be changed in the Options. The numbers will have to be written from the screen manually, but this does let you choose an appropriately rounded value, without excess precision, for the location you're capturing.
    • Google Earth 4.1 and newer can make a Google Maps URL, from which you can copy the latitude and longitude in decimal format as mentioned above. Just center the screen on your location by double-clicking on it, and then use the "View in Google Maps" button at the top.
    • Create a placemark (probably in the "Temporary Places" folder). Right-click or control-click on the placemark; one of the options is "Copy". Copy the placemark and paste it back to a text editor. The result is a KML ("Keyhole Markup Language") description of the placemark, and since KML is XML, it's easily manipulable. Towards the bottom of the placemark is a tag <coordinates>...</coordinates> which contains the long/lat coordinates in decimal degrees. Note that the order of the coordinates is reversed from the lat/long you were expecting; you have to swap them when you extract them. Also note that the precision is ridiculously high; you'll probably want to trim it down.
    • Install the Google Earth version of the hjl_get_Coor tool: Ald-Hjl-Koord-en.kmz. Once it's installed, a crosshair icon appears in the middle of the Google Earth screen. Move the view so that the crosshair is on your desired location, and then click on it. There is a link to the hjl_get_Coor tool, which gives the coordinates back in your chosen wiki markup that can be copied and pasted to an article.
    • The Picasa application allows seamless integration with Google Earth to tag sets of images saved on the computer. Select the images to tag on Picasa, and then choose "Tools / Geotag / Geotag With Google Earth". Google Earth opens with first of the chosen images in the bottom right corner, and a crosshair in the middle of the screen. Move the view so that the crosshair is on top of the desired location, and click on the Geotag button. A placemark will be added to your Temporary Places folder, from where you can normally copy it in kml format as explained above. Clicking Done will return to Picasa, which can export the data in kmz at any later date.[5] [6]
    • The exported kml or kmz file can also be converted to templates using the kmlconvert tool.
  • Various Google-based tools can be used to find latitude and longitude coordinates, such as the following: [7], [8], and [9].

OpenStreetMap[edit]

OpenStreetMap can be used; simply navigate to the desired point by double-clicking on it, select the "share" icon from the top-left toolbar, copy the "link" URL (N.B. not the shortlink) and extract the coordinate values from it.

For example, http://www.openstreetmap.org/?lat=52.54341&lon=-1.91035&zoom=15&layers=M includes a latitude of 52.54341 and a longitude of -1.91035.

World Wind[edit]

NASA World Wind can access a large online database of U.S. and global placenames (cities, villages and other geographic & anthropogenic features). Street addresses can be found using Yahoo and Virtual Earth geocoders (works for the US, Australia, UK, Japan... and maybe some other countries). (Offline search requires this pack http://www.worldwindcentral.com/wiki/Add-on:Classic_Placenames_cache_pack) Press Ctrl-F, enter the official place name, click Search, you will probably find the place you're looking for. Click Go. (of course you can navigate to the desired spot with your mouse; select View->Show Position to see the coordinates) Press Ctrl-C to copy the decimal coordinates. Paste it into Wikipedia. Example: For Tucson International Airportworldwind://goto/world=Earth&lat=32.11611&lon=-110.94109&alt=24389"

Within Wikipedia[edit]

Specific countries/places[edit]

Add to article[edit]

Finally, add the coordinates to the relevant article:

Quick how to
To add 57°18′22″N 4°27′32″W / 57.30611°N 4.45889°W / 57.30611; -4.45889 to the top of an article, use {{Coord}}, thus:
{{Coord|57|18|22|N|4|27|32|W|display=title}}

These coordinates are in degrees, minutes, and seconds of arc.

'title' means that the coordinates will be displayed next to the title.

To add 44°06′43″N 87°54′47″W / 44.112°N 87.913°W / 44.112; -87.913 to the top of an article, use either
{{Coord|44.112|N|87.913|W|display=title}}

or

{{Coord|44.112|-87.913|display=title}}

These coordinates are in decimal degrees.

  • Degrees, minutes and seconds must be separated by a pipe ("|").
  • Map datum must be WGS84 (except for off-earth bodies).
  • Avoid excessive precision (0.0001° is <11 m, 1″ is <31 m).
  • Latitude (N/S) must appear before longitude (E/W).
Optional coordinate parameters follow the longitude and are separated by an underscore ("_"):

Other optional parameters are separated by a pipe ("|"):

  • display
    |display=inline (the default) to display in the body of the article only,
    |display=title to display at the top of the article only, or
    |display=inline,title to display in both places.
  • name
    name=X to label the place on maps (default is PAGENAME)

Thus: {{Coord|44.117|-87.913|dim:30_region:US-WI_type:event

|display=inline,title|name=accident site}}

Use |display=title (or |display=inline,title) once per article, for the subject of the article, where appropriate.

See also[edit]