June 2025 photo from a FaceBook page

Photo contributed 6/25 by JGl.

Perhaps the most unusual Keystone yet found, this one is not a Town or Stream name, but one intended to notify viewers of a Historical sign/marker up ahead.   The William Penn marker so noted was not another of the Keystones, but is believed to be a much older marker that was part of many installed 20 or so years earlier by the PA. Historical Commission.  The Commission was a forerunner of today’s PA Historical and Museum Commission.  The second photo above is believed to be the William Penn marker noted on this Keystone.  It is uncertain if this William Penn marker is still existant.