Venkateswara   also known as 
Srinivasa, 
Balaji and 
Venkatachalapati  is a form of the Hindu god Vishnu. 
Venkateswara
 means "the lord who destroys the sins of the people". According to the 
Hindu scriptures, Vishnu, out of love towards his devotees, incarnated 
as 
Venkateswara and appeared for the salvation and upliftment of humanity in this Kali Yuga age. It is considered the supreme form of Vishnu in this age. The Venkateswara swami temple is also called 
Kaliyuga Vaikuntam.
The story of  Lord Venkateshwara with Goddess Padmavathi:
 The rishis
 headed by Kasyapa began to perform a sacrifice on the banks of the 
Ganges. Sage Narada visited them and asked them why they were performing
 the sacrifice and who would be pleased by it.  Not being able to answer
 the question, the  rishis approached Sage Bhrigu. To reach a 
solution after a direct ascertainment of reality, Sage Bhrigu first went
 to Satyaloka, the abode of Lord Brahma. 
At
 Satyaloka, he found Lord Brahma, reciting the four Vedas in praise of 
Lord Narayana, with each of his four heads, and attended upon by 
Saraswati. Lord Brahma did not take notice of Bhrigu offering obeisance.
 Concluding that Lord Brahma was unfit for worship, Bhrigu left 
Satyaloka for Kailasa, the abode of Lord Shiva. 
 At
 Kailasa, Bhrigu found Lord Siva spending his time pleasantly with 
Parvati and not noticing his presence. Parvati drew the attention of 
Siva to the presence of the sage.  Lord Siva was furious at Bhrigu's 
intrusion and tried to destroy him. The sage cursed Lord Siva and left 
for Vaikuntam. 
At
 Vaikuntam, Lord Vishnu (also called Srimannarayana) was reposing on 
Adisesha with Sri Mahalakshmi in service at His feet. Finding that 
Srimannarayana also did not notice him, the sage was infuriated and he 
kicked the Lord on His chest, the place where Mahalakshmi resides. 
At
 once, Lord Vishnu hastened to apologise to the angry sage and pressed 
his feet to allay the pain caused to Bhrigu's leg. In doing so the Lord 
removed the eye in the foot of the sage, which gave Bhrigu power as to 
defy the Devas. Thereupon, the sage decided that Lord Vishnu was the 
most supreme of the  trimurthis and told the  rishis the same. Thereupon, they decided that Lord Vishnu was the fruit of the  yaga. 
Sri
 Mahalakshmi was angered by the action of her Lord in apologising to 
Bhrigu who committed an offence. She, therefore, left Vaikuntam without 
heeding the entreaties of the Lord.
At the commencement of the current  Sveta Varaha Kalpa,
 the whole universe was filled with water and the Earth was immersed in 
it. Lord Vishnu assumed the form of a white boar (Sri Varaha) and dived 
into the water to lift the Earth. He slew the demon Hiranyaksha who was 
obstructing Him and rescued the Earth. 
Brahma
 and the other Devas praised Sri Varaha for saving the Earth by chanting
 the Vedas and showering flowers on Him. Lord Vishnu decided to stay on 
Earth in the form of Sri Varaha for some time, to punish the wicked and 
protect the virtuous. The place then came to be known as  Varaha Kshetra and the vVaraha Kalpa commenced.
After the departure of 
Mahalakshmi, a forlorn Lord Vishnu left Vaikuntam and took abode in an 
ant-hill under a tamarind tree, beside a  pushkarini on the Venkata Hill. 
 Taking pity on Lord Vishnu, Brahma and Maheshwara decided to assume the forms of a cow and its calf to serve Him
Surya,
 the Sun God informed Mahalakshmi of this and requested her to assume 
the form of a cowherdess and sell the cow and calf to the king of the 
Chola country. 
The
 king of the Chola country bought the cow and its calf and sent them to 
graze on the Venkata Hill along with his herd of cattle. Discovering 
Lord Vishnu on the ant-hill, the cow provided its milk, and thus fed the
 Lord.  
Meanwhile, at the palace, the cow was not yielding any milk, for which the Chola Queen chastised the cowherd severely. 
To
 find out the cause of lack of milk, the cowherd followed the cow, hid 
himself behind a bush and discovered the cow emptying her udder over the
 ant-hill. 
Incensed
 over the conduct of the cow, the cowherd aimed a blow with his axe on 
the head of the cow. However, Lord Vishnu rose from the ant-hill to 
receive the blow and save the cow. 
When the cowherd saw the Lord bleed at the blow of his axe, he fell down and died of shock.
On the death of the cowherd, 
the cow returned, bellowing in fright and with blood stains all over her
 body, to the Chola King. To find out the cause of the cow's terror, the
 King followed her to the scene of the incident. 
The
 King found the cowherd lying dead on the ground near the ant-hill. 
While he stood wondering how it had happened, Lord Vishnu rose from the 
ant-hill and cursed the King saying that he would become an  asura because
 of the fault of his servant. The King pleaded innocence, and the Lord 
blessed him by saying that the curse would end when the Lord was adorned
 with a  kireetam presented by Akasa Raja at the time of His marriage with Sri Padmavati. 
Thereafter, Lord Vishnu or 
Srinivasa, decided to stay in Varaha Kshetra, and requested Sri 
Varahaswami to grant Him a site for His stay. His request being readily 
granted, Srinivasa ordained that a pilgrimage to His shrine would not be
 complete unless it is preceded by a bath in the Pushkarini and  darshan of Sri Varahaswami, and that  puja and  naivedyam should be offered to Sri Varahaswami first.  

 
 In a nearby kingdom ruled King Akasha Rajan.  
Childless for many years, he had one day found a beautiful baby girl 
sleeping on a golden lotus in a golden box while ploughing the fields.  
He had named her Padmavathy.  A beautiful and accomplished girl, 
Padmavathy had been granted a boon in her earlier birth that she would 
be married to Lord Vishnu.  One day, Vishnu, who had been renamed 
Srinivasan by his devotee and foster mother Vakuladevi, went hunting in 
the forest.  His wandering led him to a garden with a pond.  Srinivasan 
was thirsty and tired.  After drinking from the pond, he rested in the 
shade of a tree.  Soon the soft singing of Padmavathy who was dancing in
 the garden with her companions roused him.  He was stunned by her 
beauty and drawn to her.  She too seemed to be drawn to him, but the 
angry attendants thinking him a mere hunter drove him away.
Depressed and unhappy he poured his troubles out to 
Vakuladevi.  Now for the first time, he revealed to her who he really 
was and also told her the story of Padmavathy.
In the meanwhile, Padmavathy was dreaming of 
Srinivasa.  She had no idea who he really was and knew that her parents 
would never let her be married to a hunter.
Srinivasa urged Vakuladevi to approach Padmavathy's 
father, Akasha Raja, with the marriage proposal.  In the meanwhile he 
disguised himself as a soothsayer and went to the court of Akasha Raja. 
 There, he assured Padmavathy that the hunter she had fallen in love 
with was no ordinary man but the Lord and told her that the worries 
would soon be over.  Padmavathy too poured out her heart to her parents.
  At about the same time, Vakuladevi arrived with the marriage proposal.
  After consulting with the sages Akasha Raja accepted the proposal and 
invited Srinivasa to attend the wedding on Friday, the 10th day of 
Vaikasi.
Srinivasa now had arrangements to make.  He sought a 
loan of one crore and 14 lakh coins of gold from Kubera and had 
Viswakarma, the divine architect create heavenly surroundings in the 
Seshadri hills.
The day of the wedding arrived, Lord Srinivasa was 
bathed in holy waters and dressed in jeweled ornaments befitting a royal
 bride groom.  Then he set off in a procession for the court of Akasha 
Raja.  There Padmavathy waited radiant in her beauty.  Srinivasa was 
hailed with an arthi and led to the marriage hall.  There the queen and 
King washed his feet while sage Vasishta chanted the Vedic mantras.  
Soon the wedding was over and it was time for Padmavathy to take leave 
of her parents.
Together, they lived for all eternity while Goddess 
Lakshmi, understanding the commitments of Lord Vishnu, chose to live in 
his heart forever.
Tirupati, today, stands as a special place, 
commemorating the marriage between the two.  Everyday, a kalyana utsavam
 celebrates the divine union in a celebration that stretches to 
eternity.  Even today, during the Brahmotsavam at the temple, turmeric, 
kumkum and a sari are sent from the temple to Tiruchanur, the abode of 
Padmavathy.  In fact Tirupati is rarely visited without paying a visit 
to Tiruchanur. 
In the light of this background, it has become the 
favored destination of many newly wed couples who pray for a happy 
wedding - a wedding like that of Srinivasa and Padmavathy.