Mahabharata 12.289.51
यथा कश्चिद्वनं घोरं बहुसर्पसरीसृपम्श्वभ्रवत्तोयहीनं च दुर्गमं बहुकण्टकम्
yathā kaścidvanaṃ ghoraṃ bahusarpasarīsṛpamśvabhravattoyahīnaṃ ca durgamaṃ bahukaṇṭakam
Our plain-language meaning of this verse is waiting for scholar review.
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