Valmiki Ramayana Aranya Kanda Sarga 11 Shloka 84
Original Shlokaनाम्ना चेयं भगवतो दक्षिणा दिक्प्रदक्षिणा। प्रथिता त्रिषु लोकेषु दुर्धर्षा क्रूरकर्मभिः।।3.11.84।।
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प्रदक्षिणा very considerate place, इयम् दक्षिणा दिक् on the southern side, भगवतः of the Lord (Agastya's), नाम्ना by name, त्रिषु in three, लोकेषु worlds, प्रथिता famous, क्रूरकर्मभिः by men of wicked deeds, दुर्धर्षा unassailable.
The southern side favourable to the people was famous by the name Agastya in the three worlds and stood unassailable to the demons.