Zhangjiajie, located in the northwest of Hunan Province, China, possesses an amazing scenery treat for the world. It is roughly a 2-hour flight from Shanghai or almost 2-½ hours if coming from Beijing.
For international travelers, the most common flight routes will make a stopover in major cities of China such as Beijing, Shanghai, Hong Kong, etc. Hence, I suggest you arrange a trip to those interesting entry cities first and spend a few days there, then you can either book a flight or train ticket to Zhangjiajie.
I suggest you check Kayak (click HERE) as they usually offer cheap flight rates compared to other booking sites.