Valmiki Ramayana Aranya Kanda Sarga 37 Shloka 11
Original Shlokaकैकेय्याः प्रियकामार्थं पितुर्दशरथस्य च। हित्वा राज्यं च भोगांश्च प्रविष्टो दण्डकावनम्।।3.37.11।।
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कैकेय्याः of Kaikeyi, पितुः father's दशरथस्य च and Dasaratha's, प्रियकामार्थम् to satisfy their desire, राज्यम् kingdom, भोगांश्च pleasures, हित्वा after leaving, दण्डकावनम् Dandaka forest प्रविष्टः he entered.
To satisfy the desire of Kaikeyi and to fulfil his father's word he came to Dandaka forest, leaving the kingdom and all royal pleasures, behind.