Vrishabhadri or Vrishabhachala – The name of Tirumala Hills in Satya Yuga

The Tirumala Hill abode of the Tirupati Balaji Temple is as holy as Vaikunta, the abode of Vishnu. It is believed that Srihari Vishnu had brought the sacred hill to earth from Vaikunta. In different yugas, the Tirumala Hill is known by different names. It is known as Vrishabhadri or Vrishabhachala in Krita or Satya Yuga.
Krita or Satya Yuga is the first among the four yugas as per Hindu Tradition. It is the age of Truth.
Legend has it that during Krita Yuga, a demon named Vrishabhasura captured the Tirumala Hill and started performing a gruesome penance. He used to cut his head and offer it with a flower to the Narasimha Avatar of Vishnu. His head would grow back again and he continued the same terrible austerity the next day. Fed up with this terrible tapas, holy men deserted the seven hills surrounding Tirumala.
Finally, Srihari Vishnu appeared before Vrishabhasura and asked him the reason for his austerity. The demon said that he wanted to fight Vishnu.
Vishnu agreed and a terrible fight ensued. In the end, Vishnu used his Sudarshana Chakra to annihilate Vrishabhasura.
Vrishabhasura was aware that those that were killed by Vishnu attain Moksha and he asked the boon by keeping it in mind. Vishnu was pleased with Vrishabhasura and asked him to ask one more boon.
The demon asked the Tirumala hill to be named Vrishabhadri. Thus in Krita Yuga the holy hill was known as Vrishabhadri or Vrishabhachala.