Valmiki Ramayana Bala Kanda Sarga 31 Shloka 16
Original Shlokaप्रदक्षिणं तत: कृत्वा सिद्धाश्रममनुत्तमम्। उत्तरां दिशमुद्दिश्य प्रस्थातुमुपचक्रमे।।1.31.16।।
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तत: thereafter, अनुत्तमम् the supreme, सिद्धाश्रमम् Siddha asrama, प्रदक्षिणम् circumambulation, कृत्वा having made, उत्तरां दिशमुद्दिश्य towards northern direction, प्रस्थातुम् to perform journey, उपचक्रमे commenced.
Thereafter, circumambulating the supreme Siddhasrama with reverence, they (Viswamitra and the princes) commenced their journey in the northern direction.