Ocean of milk

In Hindu cosmology, the Ocean of milk (kṣīroda, kṣīrābdhi or Kṣīra Sāgara) is the fifth from the center of the seven oceans. It surrounds the continent known as Krauncha. According to Hindu mythology, the devas (gods) and asuras (demons) worked together for a millennium to churn the ocean and release Amrita the nectar of immortal life. It is spoken of in the Samudra manthana chapter of the Puranas, a body of ancient Hindu legends. It is also the place where Vishnu reclines over Shesha Naga, along with his consort Lakshmi.

"Ocean of Milk" is the English translation of the Sanskrit terms kṣīroda, kṣīrābdhi or kṣīrasāgara, from kṣīra "milk, curdled milk" and -uda, sāgara "water, ocean" or abdhi "ocean".

Hindu history also contains a story about the churning of the Cosmic Ocean in order to obtain Amrita – the nectar of immortal life. At the suggestion of Vishnu the gods, (devas) and demons (asuras) churn the primeval ocean in order to obtain Amrita which will guarantee them immortality. To churn the ocean they used the Serpent King, Vasuki, for their churning-string. For a churning pole they use Mount Mandara placed on the back of a Great Tortoise – the Kurma Avatar of Vishnu. As the gods and demons churned the sea, a terrible poison issued out of its depths which enveloped the universe. The devas and asuras approach Shiva who took the poison into his throat and swallowed it. Shocked by his act, Goddess Parvati strangled his neck and hence managed to stop it in his neck and prevent it from spreading. However, the poison was so potent that it changed the colour of his neck to blue, thereby earning him the name of Neelakanta (blue-throated one). When the Amrita finally emerged along with several other treasures the devas and asuras fought over it. However Vishnu in the form of Mohini the enchantress manages to lure the asuras into handing over the Amrita to her, which she then distributes to the devas. Rahu, an asura, disguises himself as a deva and tries to drink some Amrita himself. Surya (the sun-god) and Chandra (the moon-god) alert Vishnu to this deception. Vishnu then decapitates Rahu just as he is about to swallow the nectar, leaving only his head immortal.

...
Wikipedia