In the Nagara Khand of Skanda Purana, King Trishanku of Surya Vamsa made an odd request to the his Guru Sage Vasishtha that he would like to go to Swarga with his mortal body and that such a Yagna be performed enabling him to do so.Vasishtha ridiculed the idea and the King asked the Sage’s sons to find a way out, lest he might abandon Vasishtha as his Guru; the infuriated sons cursed the King to turn out to be a ‘chandala’of low caste. The frustrated Trishankhu in the form of a chandala left the Kingdom making way for his son Harischandra as the King and wandered in forests where he met Sage Viswamitra who took up the issue as a challenge, especially because he was a traditional competitor and enemy of Vasishtha.The Sage asked that Trishanku should first get rid of the form of a chandal and desired him to perform a Holy Pilgrimage. As both of them were set on visiting Tirthas, they reached Arbudachal (Abu) to visit ‘Achalaswar’ and met Markandeya who advised them to take a trip to Haatakeswar and take bath in the Patala Ganga there. To their great surprise, the Snaan and worship at that place did the miracle and Trishanku got rid of the curse of his becoming a chandala. Even as Trishanku was preparing to perform a Grand Yagna, the Sage approached Lord Brahma to be the Chief Guest who refused saying that it was against the realm of possibility that a human in his form could reach Swarga. This nodoubt frustrated Trishanku as also Viswamitra but the latter never gave up the effort and did harsh Tapasya to Bhagavan Siva who out of generosity granted the boon of ability to duplicate the task of Brahma’s Creation; the Sage succeeded in creating another Sun, Moon, Sky, Air, Water etc. Indeed the parallel Srishti panicked Brahma and the compromise reached was that if Brahma took Trishanku to Swarga in the latter’s mortal body; Viswamitra would refrain from making a paralell creation.
As Sage Viswamitra found the significance of Haatakeswara Kshetra where Trishnaku’s curse of becoming a Chandala was washed off, the Sage concentrated on this Kshetra only and stopped visiting other Kshetras like Kurukshetras. The word had gone round and many Munis established their Ashrams there. In fact the Place became so famous that many Pilgrims had dips in the Patala Ganga Tirtha and worshipped Haatakeswar and even without performing Yagnas, Vratas, Charities and Yatras to other established Kshetras, devotees found it easier to visit Haatakeswar and secure Swargaloka! Having noticed this, Devas were not receiving their share of Yagnas and devotees stopped Karmik activites and made huge influx to Haatakeswara. Vayu Deva closed the traffic links after getting Indra’s permission to cover up the route to Haatakeswar and there was highly a confidential approach through ‘Nagabila’in Nagaloka in exceptional cases only in a roundabout unknown manner. As Indra had killed Vristrasura who was a Brahmana, he became a victim of the Sin of Brahmahatya and at one stage even attempted suicide by jumping from a mountain top; but a Celestial Voice advised him to pay homage to Hatakeswara Linga after purifying in Patala Ganga nearby the Kshetra through the Nagabila to absolve him from the Brahmahatya sin.Thus Indra got rid of his great sin and regained his throne.