The clan was noted for its fierce independence from the Hiraizumi-based Northern Fujiwara, but became vassals of the Utsunomiya, the lords of Shimotsuke Province, from the 11th century.

However by the 1580s, the Hōjō clan had largely defeated the Utsunomiya and had extended their hegemony into the northern Kantō region.

The Utsunomiya survived, but were ordered by Toyotomi Hideyoshi to destroy all secondary fortifications within their territories, which included Tobiyama Castle.

River cliffs with a height of 25 meters on the western and northern sides provide a natural defense.

Adjacent to the park, the Tobiyama History Museum has displays of artifacts discovered, and provides an explanation of the historical context of the site.