This is kind of funny if you are familiar with Alberta backroads. In rural areas where there are dirt roads there are often roads that are not even gravel. What looks like a solid surface might not be. A quick short rainfall can turn some of these roads into a quagmire. Four wheel drive is not going to help you either.
This one is great as well. My backroads atlas sometimes brings me to roads that ceased being roads. I appreciate that someone put up a sign.
One of the best ones I saw on some open prairie in a remote corner of Alberta said "Not Recommended For Winter Travel". It was the middle of summer and it looked like a goat trail and I would not have recommended it for summer travel either. I should have got a photo of that.