I dont believe in ghosts, but did have something happen to me that made me question my non-belief.
When I was in my late teens, my friends and I would go park on this old farm road in Springfield we called "The Y" to smoke the hippy lettuce. Right across the road there was a big field a guy I went to high school with dumped another guy's body that I went to high school with after he shot him. That has nothing to do with this story though.
Anyway, one night we were out there getting ripped and we heard what sounded exactly like a human baby crying. We were trying to follow the sound and it sounded like it was coming from under a near-by bridge. It kept crying and crying so we pulled the car up so we could aim the headlights under the bridge. We didnt see shit but the crying kept getting louder. We started getting scared so we left.
About a month later I was at another friends house (he lived with his grandparents) and was telling him about it. His granddad was in another room listening. He came into the room holding an old newspaper. It turns out my friend's granddad was a detective in Springfield in the 50's. He asked exactly what bridge I was talking about and when I told him he handed me the paper. Sometime in the early 50's a woman threw her 3 month old baby under that same bridge and left it there. It wasnt found until a few weeks later and was obviously dead. My friend's granddad was the lead detective on the case and kept that newspaper all these years.
My friend kept saying it was probably some kind of animal but I know the difference between a baby cry and an animal cry. I didnt sleep at all that night and didnt sleep well for a couple weeks.