Valmiki Ramayana Sundara Kanda Sarga 26 Shloka 17
Original Shlokaकामं मध्ये समुद्रस्य लङ्केयं दुष्प्रधर्षणा। न तु राघवबाणानां गतिरोधो भविष्यति ।।5.26.17।।
1 source checked for this shloka
समुद्रस्य ocean's, मध्ये in the middle, इयम् this, लङ्का Lanka, दुष्प्रधर्षणा unassailable, तु but, राघवबाणानाम् by the arrow of Rama, गतिरोध: resist, न भविष्यति will not be.
"This Lanka in the middle of the ocean is unassailable. But there is nothing which can resist the arrows of Rama.