Valmiki Ramayana Aranya Kanda Sarga 47 Shloka 29
Original Shlokaलङ्कानाम समुद्रस्य मम मध्ये महापुरी। सागरेण परिक्षिस्ता निविष्टा नगमूर्धनि।।3.47.29।।
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लङ्का नाम by name Lanka, मम my, महापुरी great city, समुद्रस्य of the sea, मध्ये in the middle, सागरेण by sea, परिक्षिप्ता surrounded, नगमूर्धनि on the peak of a mountain, निविष्टा it is situated.
My great city called Lanka is on the peak of a mountain surrounded by, and in the middle of, the sea.