Our preschool is a about a mile away and I walk my 3 year old there in the pushchair. We always like to do a long walk at the weekend and also use it then. In our experience of letting him walk, it's not always easy. He walks a bit and then is desperate to be held. I worry about letting him walk all the way to pre school as it's early morning and I imagine I'd have to add about half an hour of journey time on. I'm not concerned about him getting enough exercise as we do let him run around plenty and play. I'm just worried that I really should have ditched the pushchair by now.