Following a major magma flow 20 000 years ago, a natural dam formed at the foot of the south face of the Nantai volcano, leading to the creation of Lake Chuzenji and the superb Kegon Waterfall. The waterfall is visible from a terrace located in the upper part and from platforms arranged in the lower part. The main 97m waterfall never freezes; it flows at a rate of one ton of water per second into a vast corrie of steep cliffs. Twelve other small waterfalls from underground flows join it.