Valmiki Ramayana Ayodhya Kanda Sarga 3 Shloka 31
Original Shlokaस तं कैलासशृङ्गाभं प्रासादं नरपुङ्गवः।।2.3.31।। आरुरोह नृपं द्रष्टुं सह सूतेन राघवः।
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नरपुङ्गवः best among men, सः that, राघवः Rama, नृपम् the king, द्रष्टुम् to see, सूतेन सह accompanied by charioteer Sumantra, कैलासशृङ्गाभम् as lofty as the peak of Kailasa, तम् प्रासादम् that palace, आरुरोह ascended.
Best among men, Rama accompanied by charioteer Sumantra ascended that palace that was lofty as the peak of Kailasa mountain in order to see the king.