Icon viewers:

Last night Lima Senior played in Miamisburg on Harmon Field.  Years ago I took the Lake Shore Limited from Toledo to Chicago passing through a town to this day I do not know that had a Harmon Field along the tracks. 

I knew then that Wapak and Greenville also have Harmon Fields.   After that trip learned that most, if not all, of these are a consequence of Lebanon Ohio born real-estate developer William Elmer Harmon's philanthropy to those projects. (http://www.serendipityrancher.com/harmonfieldhx.htm)
 
I've often wondered how many Harmon Fields are in Ohio (or even the country) and thought you would be in a good position to open the notion up to your readers and see those they could list beyond the ones I've listed.

Steve Burkholder