The Creation of a Mountain Range
The Minami Alps were shaped by the same events that created the islands of Japan, but this is one of the few mountain ranges in the country that is of tectonic, rather than volcanic, origin.
About two million years ago—around the same time early humans first appeared—there was a time of violent geological activity. Tectonic plate movements pushed up a 2,000-meter-deep layer of mud and volcanic ash that had been on the ocean floor for over 15 million years, creating the Minami Alps.
Around one million years ago, the mountains had already reached 1,500 meters in height. The taller peaks continued to rise as they were sharpened by the glaciers of the ice age which began some 115,000 years ago, while lower peaks and surrounding landscapes were rounded and smoothed by the ice.
Visitors can still see reminders of this ancient time in the bedrock hollows created by glacial erosion and in the animals and plants that evolved to survive this cold period of Earth’s history.
A View from Above
Over 70 percent of Japan is mountainous, with numerous mountain ranges of volcanic origin, like the Kita Alps, a rugged range known for deep snows in winter, or the smaller Chuo Alps farther south. When seen from a bird’s-eye view, it is clear that the Minami Alps are quite different from their more northern brethren.
The Minami Alps are wider and seem to fold into each other, building up to a string of high peaks, none of which is volcanic. Instead, they were formed by tectonic forces that continue to push the Alps up about 4 millimeters each year, one of the fastest rising mountain ranges in the world.
Immediately to the east of the Minami Alps is the Itoigawa-Shizuoka Tectonic Line, a major fault line that has caused a series of large earthquakes. The Fossa Magna, a huge rift running from north to south, is just east of the fault. The northeast side of the rift sank, creating the vast Kanto Plain where Tokyo is located. Along the western side of the Fossa Magna, a string of volcanoes stretches from the coast of the Sea of Japan to nearby Mt. Fuji, then along the Izu Peninsula and out into the Pacific.
Home to the Highest Peaks
Mt. Kitadake (3,193 meters) is Japan’s second tallest mountain and is the gem in the crown of the Minami Alps. However, the mountain range has another ten peaks over 3,000 meters in height:
- Mt. Ainodake, 3,189 meters
- Mt. Warusawadake, 3,141 meters
- Mt. Akaishidake, 3,121 meters
- Mt. Nakadake, 3,084 meters
- Mt. Maedake, 3,068 meters
- Mt. Shiomidake, 3,052 meters
- Mt. Nishinotoridake, 3,051 meters
- Mt. Senjogatake, 3,033 meters
- Mt. Notoridake, 3,026 meters
- Mt. Hijiridake, 3,013 meters
