Valmiki Ramayana Ayodhya Kanda Sarga 5 Shloka 5
Original Shlokaस रामभवनं प्राप्य पाण्डुराभ्रघनप्रभम्। तिस्रः कक्ष्या रथेनैव विवेशमुनिसत्तमः।।2.5.5।।
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सः मुनिसत्तमः that foremost of ascetics, पाण्डुराभ्रघनप्रभम् shining like a mass of white clouds beaming with brightness, रामभवनम् abode of Rama, प्राप्य having reached, तिस्रः three, कक्ष्याः yards, रथेनैव mounted on the chariot itself, विवेश entered.
Having crossed the three courtyards in the chariot, that foremost of ascetics (Vasistha) entered Rams's abode, shining like a mass of white clouds.