Makiko Iwafuchi, 49, of Chiba, said she left her hotel on 25 May for a stroll near the Goshainkunda lake but lost her way.
She said she walked for days until she heard voices. "I screamed, saying, 'Hello! Please help me!"' she said. "It was a miracle. I felt at ease and thanked God."
Apart from some insect bites, she appeared in good health three days after her ordeal.