I would have to double check the age, but the cut off might be 10. I know most were around 4-7. I did see one tall girl, not sure how old she was. They all seemed to have a good time though.
My daughter did it at age 10 and had a great time and didn't stand out at all. She was so bummed that that was her last year. She would have done it again at age 11 if she could.
Honestly, my 6 year old son would probably like this! I just booked the Pirate Cruise at the GF for him, though. Just another idea for those looking for a special something.