Every year they turn Knotts Berry Farm in southern California into Knotts Scary Farm, and it is amazing. I haven't been in years, but they would have around 20 haunted houses, almost every one done extremely well. They also would have a ton people in costumes around the park jumping out of bushes, screaming and basically just terrorizing anyone gets near them. Plus when I went they also had some great outdoor shows, I remember one of the shows I saw had Jason, Freddy, Chucky and a few other famous horror monsters came out on stage and killed a bunch of annoying pop culture icons like Barney, N-Sink, and Britney Spears.
I remember one of my friends was acting really tough and saying that theres no way he would get scared, and he was right for the first few haunted houses, but then 15 foot tall reaper came flying out over our heads and he went running and screaming like a little girl. Good times.