How Can I Determine What Counties I Travel Through On a Trip?

but there may be one out there. I do know that the state maps that you could get from at the rest areas in Ohio had the counties printed on them. I don’t know about other maps though.
Just checked: AAA maps also have the counties printed on them.

there are markers on the highways as you go from one into another county. Doesn't interest me but to each their own.

Now having said that it seems to me that sometime within the last 5 - 6 years there was some file like that available on the factory.
Can't remember the name though. Maybe someone else can.

There is a file available on poifactory that has county lines listed. The only limitation is that you must do your travel in Texas. See the following:

http://www.poi-factory.com/node/48170

Also, I found this on the internet.

County Overlays - NO5W
www.no5w.com/CQxCountyOverlays.php
Each of the links below provides access to a Google map containing
overlays of the counties in the state. Use of these overlays provides one of three possible methods, for obtaining the lat/lon of a county line crossing point -- click on the desired point to see the lat/lon coordinates which you can paste into a text file.

http://www.gmaptool.eu/en/content/usa-osm-topo-routable

I occasionally download routable topo maps from this site and use them in my Garmin GPSr's. They show county lines and names along with a lot of other useful information.

The maps are free to download but donations are appreciated.

Amateur radio county hunters did have a map overlay for all counties, when you add it to your garmin device, it would show you the county you were entering

have not been able to find the link

We do in PA on most main roads and highways, but, if you blink while going 70mph on the interstate, you'll miss them.

example: https://i.postimg.cc/Nj8BLP16/bucksco-sign.jpg

.

Thanks for the link