In this picture you can see the gate to one of the shrines in Shimogamo-jinja.
When visiting a shrine in Japan you should show respect. If you are sick you are not supposed to visit the Shrines, because sickness is a sign of impurity.
In the shrines you will find an offering box, where you can throw a coin. After that, you are supposed to bow twice, clap your hands twice, bow again, and say a short prayer. If you see a gong, you can use it in order to get the attention of the Kami, or Shinto God.
Shinto, or the Way of the Gods, is a Japanese original faith. Shinto does not have a founder or sacred scriptures. Shinto gods are forces of nature, such as mountains, rain, trees, rivers and wind.