There is a primeval forest of beech trees by the upper portion of the Kuroson river which is the clearest tributary of the Shimanto River. The crystal clear water in the gorge reflects the beautiful autumn foliage, making for a spectacular scene. Descending to the river bank allows you to get closer to the foliage. The Kuroson River was selected as one of the best 100 natural water sources in the Heisei Period.