Located in Shiso City, Hyogo Prefecture, Iwa Shrine has long been worshipped as the Ichinomiya, the highest-ranking shrine in Harima Province (present-day southwestern Hyogo Prefecture). Its founding is very old, and according to the shrine's tradition, it dates back to around 131 AD. The main deity is Oonamuchi-no-kami, who is known for a wide range of benefits such as matchmaking, safe childbirth, recovery from illness, and protection of agriculture. In particular, since it enshrines the same Okuninushi-no-mikoto as the nationally famous Izumo Taisha Shrine, many worshippers visit the shrine as the god of matchmaking. The grounds are spacious and surrounded by dense trees, creating a quiet and solemn atmosphere.

The main deity is Oonamuchi-no-mikoto, a god who appears in the Kojiki and Nihon Shoki, and is considered the god of the land, industry, and traffic safety.

The main hall is in the irimoya-zukuri architectural style, and was once built as the main hall of the former Kokuhei-chusha Shrine. It is designated as a tangible cultural property of Hyogo Prefecture or Shisō City. Its solid construction and beautiful decoration are one of the highlights.

The grounds are famous as a power spot, with a sacred tree that is said to be over 1,000 years old and a spring of "Gosui" water that has been believed to be a sacred water since ancient times. In particular, the pure water of the Gosui is said to purify the mind and body, and many worshippers take it home with them. Another attraction is that you can enjoy the beautiful scenery of the four seasons, and the beauty of the shrine is even more prominent during the season of new greenery and the season of autumn leaves, making it popular with photography enthusiasts.

There are tourist spots scattered around the area where you can enjoy nature, such as "Hara Fudo Falls," which was selected as one of the 100 best waterfalls in Japan. At the entrance, there is also "Harima Ichinomiya Roadside Station," where you can enjoy local specialties.