Valmiki Ramayana Yuddha Kanda Sarga 39 Shloka 20
Original Shlokaनिविष्टातत्रशिखरेलङ्कारावणपालिता ।।6.39.20।। शतयोजनविस्तीर्णात्रिंशद्योजनमायता ।
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तत्र there, शिखरे on top of the peak, रावणपालिता ruled by Ravana, शतयोजनविस्तीर्णा a hundred yojanas in breadth, त्रिंशद्योजनम् thirty yojanas, आयता long, लङ्का Lanka, निविष्टा experienced.
Lanka ruled by Ravana was a hundred yojanas in breadth and thirty yojanas in length was seen.