Valmiki Ramayana Yuddha Kanda Sarga 41 Shloka 53
Original Shlokaवानरैर्बलवद्भिश्चबभूवद्रुमपाणिभिः ।।6.41.53।। सम्वृतासर्वतोलङ्कादुष्प्रवेशाऽपिवायुना ।
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द्रुमपाणिभिः with uprooted trees, बलवद्भिः might, वानरैः Vanaras, सर्वतः everywhere, सम्वृता occupied, लङ्का Lanka, वायुनापि even for wind, दुष्प्रवेशा difficult to enter, बभूव appeared.
Mighty Vanaras holding uprooted trees occupied everywhere and it seemed difficult for even wind to enter Lanka.