Matsya Purana 115.18

115.18

vyavasāyadvitīyastu pad‌bhyāmeva mahāyaśāḥ.
draṣṭuṃ sa tīrthasadanaṃ viṣayānte svake nadīm..
airāvatīti vikhyātāndadarśātimanoramām.. 115.18 ..

That far-famed king, with his own enterprising spirit as the only companion, went on foot to that home of all the tîrthas (i.e., Himâlayas), and at the end saw the renowned and beautiful river Airâvatî.—18.