Satellite Imagery is sufficient, especially if the "historical" object that should be visible is no longer visible.

Deletion is not a problem. We have people looking at deletions and if all else fails, people re-add things that are visible in satellite imagery - hence the same thing applies for deleting private roads.  Yes they will disappear for a while, but they will come back.

In this case as it's historical, it won't come back, and it's fine because it's not coming back.
