As per purana Lord Shiva's son Subramanya killed the Tarakasura. It is believed that the Shivalingam shattered into five pieces was a massive one, and the biggest of the five pieces is a fifteen feet long white marble which is worshipped as Amareswara at the Amaravati temple.
Lord Amareswara temple at Amaravati is 30 km from Vijayawada and 35 km from Guntur.
The Goddess of the temple is Goddess Bala Chamundika, the consort of Lord Amaralingeswara Swamy.
At this temple,there is a red coloured patch on the Shiva lingam . The legends said that the Shiva lingam was kept growing in its size. To stop its growth; an important nail started to digging on the Shivalingam and the sacred Shivalingam starts bleeding. And that is why the red patch on the lingam.
Amararama temple or Amaralingeswara temple is
dedicated to Lord Shiva which is located in the town of Amaravati, Guntur,
state of Andhra Pradesh.
It is also located on southern bank of holy Krishna River.The holy Shivalingam at this temple is believed to
be installed by Lord Indra, the leader of all the deities.
It is one of the Pancharama Kshetras.The mythology of the temple was that during Tarakasura vadha, it is said that the Shivalingam which was present on the throat of demon Tarakasura, was divided into five pieces. The Pancharama Kshetras built in the places where the five pieces fell down.
Amararama Temple was renovated and expanded further by Vasireddy Venkatadri Naidu, the King of Chintapalli and later Dharanikota, who was a great devotee of Lord Shiva.
The other mythology was that when Vasireddy Venkatadri Naidu was in the course of putting down a revolt in his own land, he got into a situation that he needs to have recourse to a massacre of the Chenchus.
For that incident, he lost his mental peace, which could recovered only when he visit Amaravati. Vasireddy Venkatadri Naidu went to Amaravati in the year 1796, and dedicated his entire life in Amaravati. He spent his funds to construct temples for Lord Shiva and he appointed nine archakas to perform rituals to Shivalingam at Amararama temple with providing them sustenance.