Key:aerial
 aerial
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| Description |
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This key with value "yes" was originally used for survey points that have a marker visible from the air. 
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| Group: man made |
| Used on these elements |
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| Requires |
| Status: in use |
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The tag aerial=yes was originally used for survey points that have a marker visible from the air.
In the case of these survey points near Yellowknife, Canada, the marker is a giant white X painted on the ground, and the survey marker is at the intersection of the X. This serves the purpose of making it easy to align photographs that have been taken from an airplane with a known point on the ground (accurate to a few centimeters). This is very useful for aligning "Bing Aerial Imagery", or "ESRI World Imagery".
Other uses may include features that are visible on aerial imagery and that are accurately surveyed (for example, static measurement with an RTK receiver). Such places may be roundabouts, ground-level corners, etc. These points or shapes are also used for aligning Bing Aerial, Esri World or Maxar.