Great rock walls made of rhyolite and dacite exposed by erosion. The eastern side wall is a bedrock of extended columnar structure some 65m in height and approx. 200m in width. The triangular wall on the tip is formed with numerous extensions of columnar joints and platy joints, which appear like a sleeve of Japanese armor (Yoroi-no-sode) which the site was named after. There are strange-shaped rocks in the sea such as Takasu Rock and Hachinosu Rock formed by erosion.

Fossils of current marks and footprints of large mammals remain in the river/lake deposits (alternated strata composed of conglomerate, sandstone, and mudstone) settled in a sunken place near the peripheral area of the Continent during the time of early formation of the Sea of Japan.

A port developed in a natural bay, which is a fishing base around Kasumi.

One of six Sanbaso (a traditional dance dedicated to shrines) passed down in six districts in the Kasumi area. It is dedicated to an autumn festival in Kasumi Shrine. The Sanbasou is composed of three characters of Senzai, Okina, and Kurokijo. The main play scenario is common to other districts, but the chants and detailed actions are different by district.