Valmiki Ramayana Kishkindha Kanda Sarga 41 Shloka 35
Original Shlokaतत्र नेत्रमनःकान्तः कुञ्जरो नाम पर्वतः।।4.41.35।। अगस्त्यभवनं यत्र निर्मितं विश्वकर्मणा।
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तत्र there, नेत्र मनःकान्तः pleasing to the eye and heart, कुञ्जरो नाम called Kunjara, पर्वतः mountain,यत्र there,विश्वकर्मणा by Visvakarma,अगस्त्यभवनम् home of Agastya, निर्मितम् is built.
'There you will find a mountain called Kunjara pleasing to the eye and pleasing to the heart. That is the hermitage of Agastya built by Visvakarma.