Connected to the Nasu volcanic belt, this is made up about 40 volcanoes that erupted during the Quaternary Era, and signs of its activity can still be seen at places like Mt. Iwate and Mt. Yake. These geological forms are many and varied, such as aspites (shield vocanoes: Hanchimantai), konidees (stratovocanoes: Mt. Iwate, Komagatake), tholoides (bell-shaped volcanoes: Mt. Yake), aspitholoides (bell-shaped shield volcanoes: Chausudake), and others, and many have crater lakes and lava flows. Also, in thermal areas such as Goshogake Hot Spring and Tamagawa Hot Spring, volcanic action such as geysers, fumaroles, and boiling mud is still active, earning the area the nickname The Volcano Museum.