I just got back from 10 days in France.
How the French Danger Areas works is you never see the place where the speed cam is.
It will warn you about 1 to 2 KMs before and about 1to 2 KMs after you pasted the speed cam.
So you get this red bar the hold time telling you Danger Areas till you have long past the speed cam.
You will also see a sign on the side of the road or highway before you get the warning on your GPS in most cases.
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