Located upstream from Highway 345, which runs parallel to the Makomanai River, this is an unexplored area with a beautiful clear stream flowing through a deep valley. The name "Makomanai" comes from the fact that the valley is so steep that even bears turn back.

The Makomanai Forest Road, which leads to the valley, is lined with beech trees and other broad-leaved trees. The lush green of the trees in summer and the autumn colors of the leaves as they turn red and yellow throughout the valley in fall are truly spectacular. The view from the suspension bridge is especially beautiful. It is also popular for hiking and mountain stream fishing.

The end of the ravine leads to the Makomanai Course for climbing Mt. Kariba, and the Kumabari Campground, which serves as a rest stop for climbers. Traffic becomes more cautious as the road narrows past the Makomanai Dam and becomes an unpaved forest road. The forest road leading to the valley is closed for the winter from November to late June, so it is not possible to reach the valley.