Nagato Province Ichinomiya Sumiyoshi Shrine is located in Shimonoseki City, Yamaguchi Prefecture, and is one of the head shrines of the approximately 2,000 Sumiyoshi shrines nationwide. It was founded very anciently, and is said to have begun when Empress Jingu prayed for victory during her conquest of the Three Kingdoms of Korea. The deities enshrined are the Sumiyoshi Sanjin, the guardian deities of maritime traffic, Emperor Ojin, Empress Jingu, and Takeuchi no Sukune, and are widely worshiped as gods of fishing, safe navigation, and safe childbirth. In particular, due to its ancient history, it is counted as one of the "Three Great Sumiyoshi Shrines of Japan" along with the Sumiyoshi Shrines of Osaka and Hakata.

The most noteworthy feature of the shrine grounds is the main hall, which is designated as a national treasure. This main hall was rebuilt during the Muromachi period, and its architectural style is unique, called "Sumiyoshi-zukuri," and occupies an important position in the architectural history of Japanese shrines. Its linear structure and distinctive pillar arrangement give a sense of the high level of architectural technology at the time. The grounds also include a worship hall that has been designated an Important Cultural Property by the prefecture, and an approach lined with giant cedar trees, creating an overall solemn and tranquil atmosphere.