It is a place where one can view two oceans at the same time: the East China Sea on the left and the Pacific Ocean on the right.
The view is nce since it is located near the top of the mountain.
However, the location is a little difficult to find, so please be careful. Also, the road leading to the coast is currently under construction and cannot be passed through, so if you go there from Amami Airport, you will have to make a detour.