I recall seeing a small excavation of a "hidey hole" in the SUNY
College at Postdam (Potsdam, NY) anthropology newsletter that was
being investigated as part of the "underground railroad" nearby. In
nearby Malone, NY on Webster Street in the now demolished basement of
the Franklin Academy which was not allowed to be documented by an
owner three houses away with tunnel in her basement, that now blocked
off, the homeowner wonders where it went and her house has a historic
marker for a general or something outside (Malone, NY is near the
US-Canada border, also where one of the other free properties offered
for the thereafter Texas based failed 50 mile circumference
"superconducting supercollider" and sometimes home of film star/actor
Mickey Rooney, so he said on "Howard Stern"). The NPS study seemed to
center much of the activity in Syracuse, New York.