Mahabharata 3.88.3
तत्र पुण्यतमं तीर्थं प्लक्षावतरणं शिवम्यत्र सारस्वतैरिष्ट्वा गच्छन्त्यवभृथं द्विजाः
tatra puṇyatamaṃ tīrthaṃ plakṣāvataraṇaṃ śivamyatra sārasvatairiṣṭvā gacchantyavabhṛthaṃ dvijāḥ
Our plain-language meaning of this verse is waiting for scholar review.
Open in the book