These are all markers that I was able to locate by descriptions and documentation online. Most of them are verified at least via Google Street View. I also added marker that got mentioned somewhere on the internet or in publications, but that are unverified and places where the markers got removed. This is just to have them on record. Please tell me about your findings and correct me if I am wrong somewhere.
It seems that many markers got relocated due to highway expansion. Sometimes by local churches or private people. Some of them ended up on private property. Around Middlesboro, KY markers were planted on new places or displays were recreated. All thanks to the initiative of Catherine and Clyde Mayes who documented everything around the late nineties.