As I lived in the area for years I had many chances to explore the Blue Mountains. Pack your hiking boots, food and drink and don't underestimate the distances!!!!! Be prepared. There are many, many hiking trails and camp sites (free) and maps are easy to come by. The Blue Mountains are an exhilirating, mind boggling, soul soothing experience if you are willing to do just a little walking. And yes, do go in winter because the heat in summer can be oppressing and the valleys might be inaccessible due to the fire danger.