This scenic gorge starts from the Kegon Falls high in the mountains above. It was formed by a lava flow from Mt. Nantai long ago. Many people visiting this spot have reported having dreams of the deity Fudo Myoo, the greatest of the five wisdom kings of Buddhism. Fudo Myoo protects ascetics by cutting away worldly desires with his flaming sword. It is said that the sound of the water against the rocks is similar to voices chanting the mantra of Fudo Myoo.
The gorge was developed by the seventeenth-century monk Kokai, who was a disciple of Tenkai, the monk who was in charge of the construction of the Toshogu Shrine. The name of the gorge is the last phrase of the mantra associated with Fudo Myoo, kanman. The gorge was very popular in the seventeenth century. The famous haiku poet Matsuo Basho visited here in 1689.