Valmiki Ramayana Kishkindha Kanda Sarga 50 Shloka 21
Original Shlokaततस्तस्मिन्बिले दुर्गे नानापादपसङ्कुले।।4.50.21।। अन्योन्यं सम्परिष्वज्य जग्मुर्योजनमन्तरम्।
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ततः then, अन्योन्यम् one another, सम्परिष्वज्य after holding on, दुर्गे in the dense, नानापादपसङ्कुले in a place filled with several kinds of trees, तस्मिन् बिले in that cave, योजनम् yojana, अन्तरम् inside, जग्मुः went.
Holding one another's hands, they went in for a distance of one yojana inside the cave that was densely covered with several kinds of trees.