Once upon a time in Sumatra Island, there was a handsome man named Batara Guru Sahala, who enjoyed fishing so much. One day, he caught a fish. He was surprised to find out that the fish could talk. The fish begged him to set it free. Batara Guru Sahala could not bear it. He made the fish free. As soon as it was free, the fish changed into a very beautiful woman. The woman helped Batara Guru Sahala by cooking for his meals every day. Batara Guru Sahala fell in love with that fish-woman and wanted to marry her. Batara Guru Sahala promised to keep the secret that she had been a fish and would never tell anybody about it. They were married happily. After years, they had a son.     One day Batara Guru Sahala got very angry with his son. He could not control his temper. He shouted angrily and called his son "fish children'. The son was crying. He found his mother and told her about it.The mother was very angry. Batara Guru Sahala broke his promise. The mother was shouting angrily, then the earth began to shake. Volcanoes started to erupt. The earth formed a very big hole. People believed that the big hole became a lake. Today the lake is known as Toba Lake.


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