When traveling in Europe, I occasionally come across Latin inscriptions. Their ages vary greatly, and I would like to get some tools for quickly estimating their age. How can I tell if an inscription is classical or later? What should I look for in an inscription to decide whether it is classical or not?
It would be great if you could show a couple of photos and tell about their "dating signs". I am not looking for a full scientific method to date an inscription, but a quick way to reasonably guess what is ancient and what is not.
If you think there is no simple rule of thumb, please explain why so.