Valmiki Ramayana Ayodhya Kanda Sarga 54 Shloka 42
Original Shlokaसरित्प्रस्रवणप्रस्थान् दरीकन्दरनिर्झरान्। चरतः सीतया सार्धं नन्दिष्यति मनस्तव।।2.54.42।।
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सीतया सार्धम् along with Sita, सरित्प्रस्रवणप्रस्थान् rivers, waterfalls, plateaus, दरीकन्दरनिर्झरान् caverns and mountaintorrents, चरतः while wandering, तव your, मनः mind, नन्दिष्यति will be joyful.
Your heart will be filled with joy while you wander with Sita beholding rivers, waterfalls, plateaus, caverns and mountaintorrents.