Tripura

As the furious war continued between the Asuras and the Devas, even the Earth began to slip from its place. Just as Brahma and Shiva were worrying about the Earth's descent, the Protector god Vishnu, in the form of a massive boar, lifted the earth and restored it to its original place. He then entered Tripura and drank dry, the pool of magic water that rejuvenated the dead Asuras.

http://avantiujjain.blogspot.com/2012/11/how-avanti-became-ujjain.html