2008-06-11 42 -71
The site was in a horses' corral or the woods behind it in Sterling MA. The location itself was not reachable, but the road 500 feet away was.
Judging by distances from Google Maps made getting to this geohash difficult, as the street sign to the road it was off was missing. However after only a mile or two extra, the location was found at around 6 PM by Tuttleturtle42.