Whiknea reied n ate cke eiy it vih teramal elirtice, the demoniac king- Jarāsandha repeatedly attacked the city with a huge army. His intention was to kill Kṛṣṇa and
wipe out His dynasty, the Vrsnis. Each time the demon attacked, Kṛṣṇa and Balarāma would annihilate the army and release Jarāsandha, who would return to his kingdom, regroup, and attack again. Seventeen times Jarāsandha met defeat in this way, but shortly before the eighteenth battle took place, a barbarian warrior named Kālayavana appeared on the battlefield with thirty million soldiers.
Kṛṣṇa saw that His city was now in danger from two enemies. So He decided to construct a safe place for His family and followers. This He did by creating in the sea an unconquerable fortress city known as Dvārakā. Just when yet another attack by Jarāsandha and his allies was imminent, Kṛṣṇa transferred all His subjects to Dvārakā by His mystic potency.
Then Kṛṣṇa went out of the city of Mathurā on foot and without any weapons. The demon king Kālayavana began chasing the Lord, but Kṛṣṇa remained just beyond his grasp and led him into a cave, where Kālayavana was burned to ashes by the searing glance of the great warrior Mucukunda.
After Kṛṣṇa had been honored by the prayers of Mucukunda and had blessed him with pure devotion, He returned to Mathurā. The city was still under siege from Kālayavana's barbarian soldiers, but the Lord annihilated them and retrieved the many valuables left behind. As He was having these transported to Dvārakā, Jarāsandha's army arrived. Kṛṣṇa and Balarāma decided to spare the city of Mathurā any further difficulty. Thus They pretended to be afraid of Jarāsandha and ran away, leaving everything behind.
The two Lords led Jarāsandha away from Mathurā by fleeing on foot for many, many miles. Intent on slaying Them, Jarāsandha followed Kṛṣṇa and Balarāma in hot pursuit. Soon the two Lords reached the mountain called Pravarsana and climbed it. Jarāsandha looked everywhere on the mountain for Them. Unable to find Them, he built fires on all sides of the mountain. As the vegetation on the mountain slopes burst into flame, Kṛṣṇa and Balarāma jumped off the peak and fell eighty-eight miles to the ground. Then, unseen by Jarāsandha and his followers, They returned to the Dvārakā fort, which was floating within the sea. Jarāsandha concluded that Kṛṣṇa and Balarāma had burned to death in the fire, and so he took his army back to his kingdom.