The airport is in Zhangjiajie city but the scenic park is near Wulingyuan.
Wulingyuan is located at the entrance to the Zhangjiajie park. It is a small town north to Zhangjiajie about an hour drive. If you can, plan to stay there for 2 or 3 days.
This is the largest City in the area, most people train or fly to Zhangjiajie. However there are not many place to visit when staying in the city. Tianmen mountains and the Fox Fairy Show are the main ones.