My son begged me to take him starting when he was 9. I took him when he was 12. He was so scared he was crying and we left after 3 hours (he stayed in the diner the last hour while me and our friend went into a few more mazes.
To top it off, as he was running for the saftey of the diner, he stopped midway. Freddy spotted him, looked right at him and slowly razed his hand and pointed right at him as if he was next. It was a little ironic that after three years of begging me to take him, it took three hour until he was begging me to take him home.
Frankly, I think most people should wait until they are 15 or 16.