Even though the years have been rough on this old mile marker, the Ohio style National Road marker shape is still evident. But this stone never sat beside the National Road. It sat beside the faux federal highway - the Dayton & Springfield Turnpike - as it passed through Enon. The National road didn't pass through Enon and it didn't pass through Dayton, either. It did pass through Springfield (the 'S' on the marker) but not Fairfield (the 'F'). Of couse, nothing passes through Fairfield today. In 1950, it joined up with Osborn to form Fairborn.
The marker is in front of a log cabin beside the library. All this is on the south side of the street connecting Main Street (a.k.a., Dayton Road) with the large Adena mound in the town. How I missed it on three previous passes, I'll never know. A picture here provides a slightly different view.
ADDENDUM: Oct 25, 2008 - I failed to mention that I believe the plaque is incorrect in its identification of this as a Dayton-Western Turnpike Milestone. The Dayton-Western Turnpike ran from Dayton to Richmond, Indiana. This, I believe, is a Dayton-Western Turnpike marker.