There was badass old Twilight Zone episode about an ex-SS deathsquad captain that returned to the site of his old concentration camp to "remember the good old days". The site of the camp was outside a little town & totally vacant, but he ended up being visited by the ghosts of all the hundreds of people he'd killed in one way or another. They sentenced him to death by insanity, & after they remind him of all he'd done he loses his mind. It was so appropriate.
Anywhow, the episode ended with line by Rod Serling something like, "This episode is a memorial, a timeless testament to a real time on earth when man turned this world into an open grave. Into it, they poured all their reason, their sanity, their humanity. Let it not be forgotten."
Talk about haunting.