Valmiki Ramayana Kishkindha Kanda Sarga 37 Shloka 17
Original Shlokaते पदं विष्णुविक्रान्तं पतत्रिज्योतिरध्वगाः। प्रयाताः प्रहिता राज्ञा हरयस्तत्क्षणेन वै।।4.37.17।।
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राज्ञा by the king, प्रहिताः sent, ते they, पतत्रिज्योतिरध्वगाः those moving in the path of birds and heavenly bodies, क्षणेन in that moment, विष्णुविक्रान्तम् where Visnu moved about, पदम् path, प्रयाताः travelled, हरयः monkeys, वै indeed.
The monkeys ordered by the king, traversed the pathway of birds and heavenly bodies, the path Lord Visnu had trod. [Note: the sky is called Vishnupada since Lord Visnu set his foot on the sky in his incarnation as Vamana.]