An old advertisement for the now defunct Camp Idlewild lists the location as Manhannock Island.

Consulting Bizer's list, I see no Manhannock Island. Rattlesnake Gal's wonderful thread
"Winnipesuakee Camps Remembered" contains some links to old Camp Idlewild brochures. This page seems to indicate that the camp was located on Cow Island...

Is there a Cow Islander out there who might be able to explain how this island goes by two different names?
thanks in advance ~~~ McD