How old does your child have to be before he/she can go on the bigger playground?

I don't think that there's a age limit. But in all cases all children should be supervised...

I would suggest your kid be above 3 years old with supervision but 5 years old is old enough

I believe five and older would be okay. I have 7, 5 and 3 years old, and the 5 years old goes around well.