The geographical locations of place names referenced in gedcom data can be displayed using Google Maps or Google Earth. This is achieved by obtaining latitude and longitude coordinates for each place from an online geocoder.
The place coordinates may be incorporated into an HTML file for immediate display on a Google Map. Alternatively, they may be incorporated into a KML file, which can then be used to create a map or viewed using Google Earth. The KML format is a variant of XML. In order to be used in a Google Map, the KML file must available online.
When an HTML file is created to display a map, inclusion of a large number of places could prevent the map from being displayed correctly. For this reason, the program imposes a limit of 400 on the number of places which may be included in an HTML file.
Choose Map from the Tools menu to open the Create Map File dialog. You must be connected to the Internet in order to create the file.
You must select a default country, which should be the country in which most of the places in your file are located. There is no option not to select a default country, since if none is supplied, the geocoder will locate places by default in the United States. All place names in your file located in any country other than the one chosen as the default should include the name of the country in the form shown in the drop-down list. Wintree will however detect and handle some other names, such as England, Scotland, Wales and Northern Ireland, and the geocoder may recognize some others.
Recognition of placenames by the geocoder is subject to practical limitations. English parish names of the form "Sutton St. James" are at present not recognized, nor are churches such as 'St. James's Church, Sutton". Wintree attempts to handle these cases by stripping out the church name.
You can choose to save latitude and longitude coordinates within the gedcom file, and to use them again to avoid repeated calls to the geocoder. When choosing to save the coordinates, a message will inform you of restrictions under the terms of use of the geocoder. The small button with the red Delete symbol allows you to delete all the map coordinates in your file.
The locations of the different categories of events selected will be displayed on your map using differently coloured icons. When creating a KML file, you can choose to have all events displayed irrespective of date, or to have the map display a time slider, allowing you to select different historical periods and see only events which took place during those periods.
Click Save to create and save a KML or HTML file. Click View to view the file using Google Earth, provided it is installed on your computer, or a web browser respectively.
Use of the online geocoder is subject to a limit on the number of requests which may be made in one day. The facility is provided for you to supply an access key if required. A key can currently (May 2016) be obtained from the Google Maps API website at https://developers.google.com/maps/documentation/javascript/get-api-key.
Use of the geocoder is subect to terms and conditions imposed by Google.