Tomi-san is a two-peaked mountain with an altitude of 350 m above sea level located in Minami-Boso City, Chiba Pref. Being a part of Boso Kyuryo (hills), intact nature remains in the mountain, which is covered with fresh green leaves in early summer. The observatory at the top of Konpira-mine, the northern peak, is named “Juishu Ichiran Dai (the observatory of eleven provinces),” because the view from here is superior to that from “Jushu Ichiran Dai (the observatory of ten provinces)” at the top of Mt. Nokogiri. Tomi-san was used as the setting of the novel “Nanso Satomi Hakkenden” by Takizawa Bakin. On the side of the mountain, there is a cave that Fusehime, a daughter of the Satomi clan, hid herself with her dog, Yatsufusa. With the Suisen Kaido (the iris road) and Kobai Kaido (the red plum blossom road) in the vicinity, Tomi-san is also popular among hikers.