You may have visited Naritasan Shinshoji Temple which is one of the most popular temples in Japan. Since it is in 30 minute distance from Narita Airport by train & walk, you can easily visit this temple if you stay in Narita area.
What I would like to introduce you in this time is not the temple itself but "Naritasan Park" in its grounds. This is a large park where visitors can enjoy flowers of all seasons, such as plum blossoms, cherry blossoms, chrysanthemums, etc. It is located on the right hand side of the Great Main Hall of the temple. There are waterfalls, big ponds and tree-shaded walkways. You can enjoy walking in the green forest.
Yuhi-no-Taki Falls in the park.
Ryuchi-no-Ike Pond in the park
If you are interested in Japanese haiku poems, you will find stone tablets inscribed with haiku poems by renowned poets, such as Matsuo Basho and Takahama Kyoshi.
I would like you to visit this park if you have free time in Narita.
If you would like to visit the temple and its related buildings, I would recommend you to go with a guide. There are several historic buildings, but it may be difficult to understand each deeply only by the information board or a guide map.
Since I am offering 3-hour tour to Naritasan Temple, please take a look at the below website if you are interested in it.
Have a nice stay in Japan!