Mt Takao, or Takaosan, is actually inside the city limits of Tokyo. The Japanese secretary of the American we were in Tokyo to see suggested this great park to us for an outing. You can pay about ¥400 to take a funicular up the mountain, or you can hike up if you have more time. Even if you take the train, you'll still need to walk a bit before you arrive at the temples and shrines.
We happened to arrive in time to attend a Shinto-Budhhist cleansing ceremony. Make sure you take off your shoes outside the temple! The ceremony lasts about 30 minutes and includes the burning of incense, an Asian-Gregorian type of chant, drums, and a sprinkling of ashes and dirt on each participant. No cameras are allowed in the temple, but there are plenty of other things to shoot outside. Also, look for a little noodle shop just below the main temple. They had great tempura and noodles!
There are many trails to explore, and be sure to check out the very long wall of cedar planks. Each plank has the name of a donor written on it. The size of the plank is dependent upon how much the person donated to the temple and the park.