History of the Horse and Ox Rocks
This V-shaped outcropping of rock, which gives the Horse and Ox Rocks their names, is the kind of natural formation that is both historically and geologically significant.
Every Rock Tells a Story
The rocks themselves tell a fascinating story.
On the right is the Ox, composed mostly of sandstone, which means it was part of the subterranean Goto Group that forms the foundation of these islands. The Horse rock on the left is a basaltic dyke. These are the two primary materials that comprise most of the surface of the Goto Islands: on the one hand, sandstone, mudstone, and gravel from the Goto Group, materials that were deposited and accumulated when Japan was separated from the Asian mainland, and on the other, magma that was cooled down after originating inside the Earth.
Here we can see these two fundamental rock formations side by side. It appears that the basaltic rock on the left intruded, or pushed through, the sandstone on the right, and the effects of this intrusion can be seen in the sandstone.
The Origin of “Horse” and “Ox”
The unusual names have a story all their own.
Centuries ago, the Goto fief and the neighboring Tomie fief were arch rivals, competing for the natural resources of the island. To settle a dispute about who could fish and hunt and farm where, both groups sent a representative to negotiate an agreement. It is said that the representative from Tomie came via ox, while the representative from Fukue rode a horse. They met at this spot and agreed that it would henceforth be the border between the two fiefs. They also agreed to draw a line from the rocks out into the bay towards the Ojirase rocks to demarcate their respective fishing zones. Even today these rocks mark the border between the districts of Tomie and Fukue in Goto City.
