is a group of complex volcanoes located in the northeast part of Nikkà  National Park, Japan. The tallest peak is Sanbonyari Peak at a height of . Mount Nasu is one of the 100 Famous Japanese Mountains.
Mount Nasu has the following major peaks:
These peaks are known collectively as .
It is estimated that Mount Nasu started erupting 600 thousand years ago. The eruption started from the north end of the mountain range, at Kashi-Asahi Peak. Only Chausu Peak is active today.