Parāçara said:—Once on a time Krishna went to Vrindavana, without Balarāma; and there, adorned with garlands of wild flowers, roamed he, encircled by the cow-herds, He then repaired to the banks of Kalindi, undulating and sparkling with foam and as if smiling when the waves dashed against the banks. There he saw the pool with the dreadful serpent Kāliya, boiling with the fires of poison.

In plain words: One day young Krishna went to the forest of Vrindavana without his brother Balarama, wearing flower garlands and surrounded by cowherd boys. He went to the sparkling Kalindi (Yamuna) river and found a pool where the terrible serpent Kaliya lived, its water boiling with poison.