Valmiki Ramayana Kishkindha Kanda Sarga 60 Shloka 7
Original Shlokaहृष्टपक्षिगणाकीर्णः कन्दरान्तरकूटवान्। दक्षिणस्योदधेस्तीरे विन्ध्योऽयमिति निश्चितः।।4.60.7।।
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हृष्टपक्षिगणाकीर्णः inhabited by flocks of happy birds, कन्दरान्तरकूटवान् filled with caves and mountains, अयम् this, दक्षिणस्य southern side, उदधेः ocean's, तीरे on the shore, विन्ध्य Vindhya, इति this is, निश्चितः for sure.
'I came to know then that this place is inhabited by flocks of happy birds and full of many caves and mountain peaks. This is mount Vindhya on the shore of the southern ocean.