Even at school we have to be very aware of the tendency of some of our kids on the spectrum to wander off. Thankfully, the school I am at now has a fenced and gated playground which helps a bit. Each of our preschool classrooms also has a child gate at the door although that can’t be relied on to be 100% effective. It seems like some of the kids I have known on the spectrum are the best climbers I have ever seen!
I think there is a great need for more public playgrounds that are “autism friendly” – fenced, gated with safe play equipment.