Some extracts from the Varaha Purana:

The Rishis headed by Kasyapa began to perform a sacrifice (yaga) on the banks of the Ganges. Sage Narada visited them at that time and asked them to tell him 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). 

There, he found Brahma reciting the four Vedas with his four heads in praise of Lord Narayana and attended upon by Sarasvati and not taking notice of Bhrigu offering obeisance. Concluding that Brahma was unfit for worship, Bhrigu left Brahmaloka for Kailasa. 

At Kailasa, Bhrigu found Lord Siva spending his time pleasantly with Parvati and not noticing the Sage Bhrigu. Parvati drew the attention of Siva to the presence of the sage. 

Lord Siva became furious at the intrusion of Bhrigu and tried to destroy him. The sage cursed and left for Vaikuntham. 

The angry sage went to Sri Vaikuntham. Srimannarayana was reposing at that time on Adisesha with Sri Mahalakshmi at His feet in service. 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 the Lord hastened to make apologies to the angry Sage and pressed his feet to allay the pain caused to the leg. In doing so the Lord removed the eye in the foot of the Sage, which gave him power as to defy the Devas. The Sage thereupon decided that Sri MahaVishnu was the most Supreme of the Trimurtis and told the Rishis the same.They thereupon decided that Sri MahaVishnu was the fruit of the Yaga and sacrifice was offered to Him (Vishnu).

At the commencement of the present Sveta Varaha Kalpa, the whole Universe was filled with water and the earth was immersed in it. Lord Vishnu took to form of a White Boar and dived into the water to lift the earth. He slew the demon Hiranyaksha who caused obstruction to him and rescued the earth. 

Brahma and the other Devas extolled Sri Varaha at the time with the chanting of the Vedas and showered flowers on him for saving the Earth. Lord Vishnu decided to stay on Earth in the form of the White Boar for some time, to punish the wicked and protect the virtuous. This place thenceforward came to be known as Varaha Kshetra and Varaha Kalpa began from that time. 

After the departure of Mahalakshmi, Lord Vishnu left Vaikuntha in a forlorn condition and took his abode in an ant-hill on the Venkata Hill under a tamarind tree beside a Pushkarini. 

Brahma and Mahesvara, taking pity on the condition of Vishnu, made up their mind to assume the forms of a cow and its calf to serve him. 

The Sun God informed Mahalakshmi of this and requested her to sell the cow and calf to the king of the Chola country assuming the form of a cowherdess. 

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 in the ant-hill, the cow everyday emptied her under over the ant-hill and thus fed the Lord. 

Finding that the cow did not yield any milk, the Chola Queen chastised the cowherd severely. 

To find out the cause of the absence of milk, the cowherd followed the cow and hid himself in a bush and discovered the cow emptying her under over the ant-hill. 

Getting wild over the conduct of the cow, the cowherd aimed a blow with his axe on the head of the cow. But the God 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. 

On the death of the cowherd, the cow returned bellowing to the presence of the Chola King with blood stains over her body. To find out the cause of the terror of the cow the Chola King followed her to the scene of the incident. 

Near an ant-hill, the King found the cowherd lying dead on the ground. While he stood wondering how it had happened, the Lord rose from the ant-hill and cursed the king to become an Asure from the fault of his servant. Entreated by the king who pleaded innocence, the Lord blessed him by saying that His curse would end when He was adorned with the Kireetam presented by Akasa Raja at the time of His marriage with Sri Padmavati. 

Thereafter Srinivasa decided to stay in this Varaha Kshetra. He therefore 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 Darsan of Sri VarahaSwami, and that Puja and Naivedyam should be offered to Sri Varaha first. 

Yasoda brought up Sri Krishna, the son of Devaki, in his early years. Yasoda was not blessed to witness the marriage of Sri Krishna with Rukmini and she felt very sad. Sri Krishna promised to fulfil her desire in her next birth as Vakuladevi in his next Avatara as Srinivasa. This Vakuladevi was sent to serve Srinivasa by Lord Varahasvami, on whom she was attending till Srinivasa came to Venkatachala. 

Sometime after, a King named Akasa Raja who belonged to the Lunar race was ruling over Thondamandalam. He had a brother named Thondaman. Akasa Raja had no issue for a long time and so he wanted to perform a sacrifice for obtaining an offspring. While he was himself ploughing and ground for sacrifice, his plough turned up a lotus in the ground. On examining the lotus, the King found a female child in it. 

The king was happy to find a child even before he performed a sacrifice and carried it to his place and gave it to his Queen to tend it. At that time he heard an aerial voice which said "O King, tend it as your child and fortune will befall you". As she was found in a lotus, the king named her Padmavati. 

In course of time Princess Padmavati grew up into a beautiful maiden and was attended by a host of maids. One day while she was spending her time in a garden picking flowers with her maids, Saint Narada approached her. Assuring her that he was her well-wisher, he asked her to show him her palm to read her future. He foretold that she was destined to be the spouse of Lord Vishnu himself. 

At this time Lord Srinivasa, who went for hunting chased a wild elephant in the forests surrounding the hills. In the pursuit, Srinivasa was led into a garden, where Princess Padmavati and her maids were picking flowers.The sight of the elephant frightened them and their Princess. 

But the Elephant immediately turned round and saluted the Lord and disappeared in the forest.Lord Srinivasa came on horse back and saw the frightened maidens and he was accosted by them with queries. 

Lord Srinivasa had explained them about his birth and parentage. He enquired them about their princess and her parentage and birth.

When he was informed that the Princess was Padmavati (lotus-Born) the foster Daughter of Akasaraja, he loved her and made advances to the Princess. He was repulsed with stones by the maids and he urgently returned to the hills leaving the horse, which fell on the ground. 

Vakuladevi, as usual, brought dinner to Srinivasa comprising various delicious dishes. But she found him lying on his bed love-sick. She enquired the cause of his sickness. The Lord informed her that unless he secured Princess Padmavati, he would not be well. Vakuladevi then asked him to tell her all about the Princess, who she was, and how he came to love her. The Lord then narrated the story of her (Padmavati’s) previous birth and his promise to wed her. 

In olden times Lakshmi was staying as Vedavati in a Rishi Asrama in the forests. At that time Ravana, the lord of Lanka came there and tried to tempt her. Vedavati grew angry and cursed him that she would bring about his death. 

To fulfil her words, Vedavati entered into the fire but the fire-god rescued her. He took Vedavati to his house and entrusted her to his wife to take care of her. 

When Ravana was about to carry away Sita from Panchavati in the absence of Rama and Lakshmana, the Fire-God appeared on the scene and offered Vedavati to Ravana as the real Sita who was kept with him by Rama to evade Ravana. 

Ravana took Vedavati to Lanka thinking she was the real Sita, while Agni(Fire-God) took Sita to his house and asked his wife Swahadevi to look after her. 

After the destruction of Ravana, Vedavati entered the fires when rejected by Rama. Then the Fire-God offered the real Sita to Rama. Rama then questioned her as to who the other lady by her side was. 

Sita informed Rama that she was Vedavati who suffered all the tortures for her sake for ten months in Lanka and requested Rama to accept her also as his spouse. But Rama declined her request saying that he was wedded to policy of having only one wife during his life time, and he promised to wed her in her next birth as Padmavati, born as the daughter of Akasaraja when he will take the form of Srinivasa. 

There upon Vakuladevi thought that Srinivasa would not be happy unless he married Padmavati and she offered to go to Akasaraja and his queen and arrange for the marriage. On the way she met the maid-servants of Padmavati returning from a Siva Temple. She learnt from them about Padmavathi's love-sickness and went to the queen along with them. 

Akasaraja and his queen Dharanidevi became anxious about the health of their daughter. They learnt about Padmavati's love for Srinivasa of Venkata Hill. Akasaraja consulted Brihaspati about the propriety of the marriage and was informed that the marriage was in the best interests. 

After the departure of Vakuladevi Srinivasa could not rest in peace. He doubted her success in the mission. He therefore assumed the form of a Yerukula-woman and entered the streets of the capital telling fortunes. Padmavati's maids saw her and invited her to the presence of their queen. 

The maid-servants went and informed the queen that the fortune-teller was hesitating to come into the palace without an invitation from the queen. 

The queen came out herself and invited the fortune-teller into the palace.The fortune-teller was taken to the presence of Princess Padmavati. 

The fortune-teller saw the palm of the Princess and told the queen about the cause of Padmavati's indisposition and advised to give her in marriage to Lord Srinivasa. She also told the queen that a lady would approach her shortly to formally request Padmavati's hand in marriage on behalf of Srinivasa. 

After the departure of the fortune-teller, Vakuladevi went to the queen along with the maids and informed her that she came from Srinivasa to request the hand of Padmavati in marriage for him. 

Having consulted Brihaspati and heard from his queen about the prediction of the fortune-teller and arrival of the messenger, from Srinivasa, Akasaraja decided to bestow his daughter on Srinivasa and he called the palace purohits to fix a Muhurtam for the marriage. 

Akasaraja informed his Ministers and other Officials of his intention. Immediately a letter was drafted for being sent to Srinivasa requesting him to come and marry the Princess. 

Akasaraja entrusted the letter to Sukamahamunin for being delivered to Srinivasa. Suka went to Venkata Hill with Vakulamalikadevi. He presented the Patrika to Lord Srinivasa, who felt pleased and sent his garland through him for Padmavati. 

Immediately Lord Srinivasa called for a conference of the Gods to win their consent for His marriage with Princess Padmavati. 

To meet the expenses of the marriage, Kubera lent money to the Lord. 

Lord Srinivasa started for the residence of Akasaraja with his consorts and Brahma and Siva and his vehicle Garutman. 

At the entrance the Lord was received by Akasaraja with all honours and was taken in procession on a mounted elephant to the palace for the marriage. 

In the presence of all the Devas, Lord Srinivasa took the hand of the Princess Padmavati and wedded her and thus blessed Akasaraja.

Contest between Adisesha and Vayudeva

During the Dwaparayuga, Vayudeva (the Wind God) went to Vaikuntam to pay his obeisance to Lord Sri Vishnu. The Lord was reclining in the company of Sri Lakshmi. The doorway was guarded by Adisesha. Vayudeva was incensed when Adisesha prevented him from entering Sri Vishnu’s mansion. Adisesha and Vayudeva began to fight with each other. 

When Lord Vishnu intervened, each was boasting of his superior valour and supreme might. To test who was stronger, the Lord suggested that Adisesha encircle the Ananda hill, an off-shoot of the Meru mountain on its northern side, and that Vayudeva blow hard to try and dislodge the Ananda hill from Adisesha's hold. The contest waxed furiously, and as the World trembled, Brahma, Indra and the other Divine Beings requested Adisesha to yield victory to Vayudeva for the welfare of the world. 

Obliging them, Adisesha released his hold on the hill. As a result, Adisesha and the Ananda hill were blown away to the banks of the river Swarnamukhi. Adisesha was dejected by his defeat. Lord Brahma and the others appealed to him by saying that he would be merged with the hill Venkatadri and Vishnu would reside on him. Adisesha then metamorphosed into the vast Seshadri, with his hood manifesting itself as Venkatadri sustaining Sri Venkateshwara, his middle as Ahobila supporting Lord Narasimha, and his tail as Srisailam bearing Lord Mallikarjuna (Lord Siva).

Restoration of the Earth by Adi Varaha

During the eight thousand yugas (the equivalent of a day and night for Brahma, the Creator), there was a raging fire, and everything on Earth was reduced to ashes. Man had to forsake the Earth and seek refuge in Janaloka.

At the approach of night (of Brahma), Vayu, the Wind God, blew furiously. Huge clouds were formed, there was torrential rain, and it resulted in Pralaya Kalpa (the Great Deluge). The Earth sank into the Patala loka, and remained in that state for a thousand years (during a part of that night of Brahma).

Sri Maha Vishnu, wanted to rescue the Earth. He assumed the form of Adi Varaha and proceeded to Pataloka. He fought a fierce duel with Hiranyaksa and killed him. He then slashed the water and brought up the Earth on his tusks.

Brahma, the Devas and the sages extolled Adi Varaha's virtues, by chanting the Vedic mantras. They prayed to Him to re-establish the Earth as before. Adi Varaha obliged them, and called upon Brahma to recreate the world. He expressed his desire to reside on the Earth to protect its people. He commanded his vehicle, Garuda to fetch Kridachala (an extensive natural hill with lofty peaks, embedded with gold and precious stones, and which resembled Adisesha in shape) from Vaikuntam.

Garuda brought Kridachala and deposited it on a sacred spot (to the East of Swami Pushkarini) chosen by Adi Varaha. Adi Varaha stood within the divine vimana of Kridachala, which shone with many gem-studded gopuras.

Brahma and the other holy personages requested the fearsome-looking Adi Varaha to assume a tranquil and composed look, and rest on the hill to protect men and grant boons to people unable to reach God through Dhyana Yoga (meditation) and Karma Yoga (doing one's own duty).

Adi Varaha appeared with four arms and a white face. He was adorned with jewels and accompanied by Bhu Devi. He resolved to stay at Venkatadri, under a divya vimana, to grant the prayers of men.

-- Source: http://balaji.sudarshana.org