1st Horror Movie

I was just sitting here watching "It Came From Beneath The Sea" with my 3 year old grandson, when he fell asleep. While I was watching him sleep, & waiting for him to get enough asleep to put him to bed, I started thinking about when I was his age. I remember watching movies like "It Came From Beneath The Sea", "Them!", "King Kong", "The Giant Gila Monster", & movies like that with my dad. My grandson LOVES the old B/W horror movies like these. The "Big Octopus Movie", as he calls it,  is his favorite! I guess what I'm getting at, is, WHAT WAS THE FIRST HORROR MOVIE THAT YOU REMEMBER SCARING YOU? HOW OLD WERE YOU? Personally, I remember being 4 years old, and being SCARED TO DEATH by a door to a room in our basement,  because it looked like the door to FRANKENSTIEN'S lab! So, I have to say that FRANKENSTIEN was the first to scare me! So, C'mon Horror Fans! Dredge up the old, repressed,  memories & Let Me Hear From You!