Hi Vish, yes there are good paths through the top two loops at least, some are paved but most are boardwalk and gravel but there were several people with strollers when we were last there and they were getting around fine. The challenge if your 4 year old is quite active is getting them to hold your hand and stay with you, it's not a safe place for them to run off excess energy. While there are barrier fences on the big drops they are kept minimal for good visibility and you are asked to stay within the clearly defined viewing areas and paths both to avoid damaging the delicate structures but importantly for safety. I hope I don't put you off, we saw several children there, the steaming ground, bubbling mud and colours are magical for little ones.