Nara Deer Park is based in the city of Nara, in Japan, and is officially about 1,240 acres of woods and temple grounds. The park itself is inhabited by sika deer, who roam freely and are also classified as national treasures. Throughout the park are several temples and shrines, among them Todai-ji, known for being the largest wooden building in the world. If you want to explore more about the park, there are also tours you can book that are listed on TripAdvisor, although most of the park is fully open to the public.
There have been cases of tourists being injured by the deer, mostly in cases where the instructions around feeding deer were not followed. Since then there have been more signs added, explaining the hand motions deer are expecting to see, when someone is indicating if they do or do not have food. When we visited, even without knowing much about this, we saw signs and made note of their advice. We didn't run into any problems, but did step in a few times to help other people who had somehow missed the same instructions. The deer were very friendly, and not afraid of people at all, so they would approach you fairly boldly and you would need to hold up your hands, palms clearly empty, to let them know there were not tasty crackers.