Valmiki Ramayana Kishkindha Kanda Sarga 40 Shloka 65
Original Shlokaततः परमगम्या स्याद्दिक्पूर्वा त्रिदशावृता।।4.40.65।। रहिता चन्द्रसूर्याभ्यामदृश्या तिमिरावृता।
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ततः परम् beyond that, त्रिदशावृता guarded by gods, चन्द्रसूर्याभ्याम् by Moon and Sun, रहिता not present, तिमिर darkness, आवृता pervaded by, पूर्वादिक् eastern direction, अगम्या स्यात् not possible to reach, अदृश्या invisible.
'Beyond, there is no Sun or Moon. Darkness pervades. It is neither accessible nor visible. It is guarded by the gods.