KML (formerly known as Keyhole Markup Language) is an XML-based file format for displaying information in a geographic context. KML information can be drawn in many earth-based browsers, including ArcGIS Earth and ArcGIS AllSource. KML Version 2.2 has been adopted as an Open Geospatial Consortium (OGC) standard. The complete KML specification can be found at https://www.opengeospatial.org/standards/kml/.
You add KML information to maps and scenes the same way you add other data. The KML file is the source of the layer in the map or scene. You can use a .kml or .kmz (compressed) file, or a URL pointing to a KML file.
A single KML file can contain features of different geometry types and can even contain both vector and raster data. ArcGIS AllSource draws all this content as a single layer. The KML settings defined in the source file are honored. You can navigate and explore the KML information, and change a few aspects of the layer's display, but you cannot modify the KML itself.
KML elements can include information that can be viewed in pop-ups, but there is no provision for attributes for KML features. A KML layer does not have an associated attribute table. You cannot select KML features or use them in analysis. If you want to work with this data in the same way as other GIS data, use the KML To Layer tool to convert a KML (or KMZ) file into feature classes in a file geodatabase. This tool also creates a corresponding layer file that reflects the symbology established in the KML file.
Supported KML elements
Elements in a KML file are supported by ArcGIS AllSource and are reflected in the Contents pane and in the display of a KML layer. Supported elements include the following:
- 3D models
- Custom data
- Ground overlays
- Network links
- Placemarks
- Regions
- Screen overlays
- Time spans
- Time stamps
Unsupported KML elements
KML files may include elements that are not supported in ArcGIS AllSource. If these elements are present in the source KML file, they are ignored by the KML layer and don't appear in the map or scene display. They are listed in the Contents pane. Unsupported elements include the following:
- Description snippets
- Photo overlays
- Sky data
- Tours
- Tracks