Vishwamitra began the journey to Mithila with Rama and Lakshmana, accompanied by several sages from his ashram. Rama inquired about the upcoming places and forests, and Vishwamitra provided detailed answers. After crossing the Son River, they entered a beautiful state. Upon Rama's inquiry, Vishwamitra revealed that he was once the king of that state and spoke about his ancestors to Rama and Lakshmana. After resting for the night, they resumed their journey the next day. Soon they spotted a deserted and lovely ashram. Rama was curious to learn more about this place. 

"A long time ago, Sage Gautama resided in this ashram along with his wife Ahalya," narrated Vishwamitra. "This was a lovely place back then, but an unfortunate event happened one day. It was midnight, but Sage Gautama mistook the time to be Brahmamuhurta (an auspicious time) and set out to bathe in the Ganga. Indra, the king of the gods, disguised himself as Sage Gautama and went to meet Sage Gautama's wife, the ravishing Ahalya. They slept together, after which Indra ran away, only to run into Sage Gautama returning after his bath. Seeing the guilty Indra, Sage Gautama cursed him to become a eunuch. 

"The sage believed his wife was willing to participate in the deed and cursed her, 'You will become a stone statue, and no one will pay any attention to you.' 

"When Ahalya begged the sage for forgiveness, he said, 'When Emperor Dasharatha's son, Lord Rama, comes to this place in the Treta era, by the touch of his feet, you will return to your original form.' 

"Ahalya has been trapped here as a stone statue since then."

After hearing this tragic story, Rama touched the statue with his feet, and thus freed Ahalya from the curse. She returned to her original beautiful form, and Sage Gautama happily accepted her as his lawful wife. Rama's reputation spread far and wide after this incident.