Narita-san Shinsho-ji Temple is a huge temple complex not far away from Narita Airport. It is a great option if you have some time to kill before or after dropping people off or picking them up. It has been a working temple for hundreds of years and is an important site of worship to this day. You can wander around for hours and admire the different styles of architecture on display, or kick back and do some people watching at one of the many little eateries close-by. There are English leaflets available that will shed some light on what everything means and give you a good grounding on the history of the area. There is plenty more to do within walking distance and you could easily spend a day around here. It is an eye-opening introduction to Japan for the newly arrived so if you can fit it into your schedule it is a fantastic destination.
Find out more about Naritasan Temple.