Hi, Mrs.Smyth. If you go to Simatai alone, maybe it is a good choice, but since you will go there with your five years old daughter, I do not recommend Simatai to you. Because Simatai is a wild wall without being repaird. Many bricks on the wall are loosen and there are no handrails to help you go up and down in many parts. Most stairs are quite steep located beside the cliffs. I suggest you visit Badaling or Mutianyu, they are repaired walls which are safer to you and your daughter. Good trip!