midPoint
Accepts an event-station pair if the midPoint between them is within the given area. Areas can be any valid area, including BoxArea, and GlobalArea.
Example
<midPoint>
<boxArea>
<latitudeRange>
<min>35</min>
<max>35</max>
</latitudeRange>
<longitudeRange>
<min>-80</min>
<max>-80</max>
</longitudeRange>
</boxArea>
</midPoint>
Places this can be found
In eventStation there is a choice between all of the following