Donald A. Windsor
The historical Tri-Town Marker for the borders of German, McDonough, and Smithville was still in place on Sunday 7 April 2013.
It is a sandstone rock at least a foot wide, a half-foot thick and 2 feet deep, perhaps deeper.  It is hard to find, so I like to visit it every few years, just so I can remember where it is.
An article about this marker appears in my book, cited below.
Reference cited:
Windsor, D. A.  The most significant corner in Chenango County.  In:  Souvenirs of Yesteryear. Norwich, NY: self-published.  2008. 1:28-29.
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