Route 14, as it was said before.
But I have an idea: when you encounter an old man in the scary house he tells you a lame story, after that he demands a tip, and says that if you don't tip him something *haunting* or *scary* will happen. After that I didn't tip him on purpose and as I walked out of the house, the very second I got on the swampy ground I got and encounter and it was haunter, haven't met him after that.
Maybe it is just a coincidence, but it is at least worth checking out.