Valmiki Ramayana Kishkindha Kanda Sarga 67 Shloka 37
Original Shlokaएतानीह नगस्यास्य शिलासङ्कटशालिनः।।4.67.37।। शिखराणि महेन्द्रस्य स्थिराणि सुमहान्ति च।
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शिलासङ्कटशालिनः the rocks of the mountain ranges, अस्य of this, महेन्द्रस्य नगरस्य Mahendra mountain's, एतानि these, शिखराणि peaks, स्थिराणि stable, सुमहान्ति च are very huge.
'The rocks on the peaks of the ranges of mount Mahendra cannot with stand it, although they are huge and firm.