The Salem Witches Are Missing
In November of 2008 bodies were found while work crews were digging in Portsmouth, New Hampshire. Workers had stumbled onto additional remains of a slave cemetery -- first discovered in 2003, that dated back to 1705. Archeologists swooped in and collected the artifacts which had been neglectfully covered over by centuries of development in a New England community not known for its slave holding past. Perhaps if more people had remembered that the evils of slavery had played out in northern communities like Portsmouth, folks would have found the remains sooner. And if generations hadn't thought that slavery was just fine, the graves might not have been so easily and ignobly forgotten in the first place.
That "there-was-nothing-wrong-with-it" cultural norm is probably why the graves of the "Salem Witches" are lost to history as well. See, for generations after the "witches" were hanged and buried, the community -- at least the politically powerful -- thought they were well rid of these troublesome characters and neither preserved their execution site nor where their bodies were interred.
http://www.huffingtonpost.com/pat-lamarche/salem-witch-trials-_b_1905804.html