Adam`s bridge was constructed by the monkey army in order to reach the kingdom of Lanka. After Hanuman returned from Lanka with the message of Sita to Rama, Ravana called upon his council of ministers and discussed about the safety and security of Lanka and the war against them. Vibhishana, one of the younger brothers of the demon king Ravana tried to make his brother understand that war against Rama would ruin the whole of Lanka and it should be fair enough to surrender Sita to Rama. Ravana became furious and offended Vibhishana extremely and as a result of this Vibhishana along with his four faithful followers flew away from Lanka to meet Rama and Lakshmana and announced himself to be Vibhishana and told that he would like to form an alliance with Rama in order to kill Ravana. Rama accepted his proposal and in return promised him to make the king of Lanka after the defeat and death of Ravana. Then Hanuman and Sugriva and Rama took counsel with Vibhishana how to cross the ocean, and he deemed that Rama should seek the aid and the friendship of Ocean for the building of a bridge.

Rama prays to Varuna to let his army cross over to Lanka
The proposal of Vibhishana was accepted by all and Rama, spreading a couch of sacrificial grass, sat over it, facing the east, with praying hands toward the sea and told that either the ocean shall yield or he would die. There Rama sat for three days, silent, concentrated, following the rule, intent upon the ocean, but there was no answer from the Ocean. Rama then became very much angry and rose up and took his bow, and threatened to dry up the sea and lay the home of Varuna bare. He loosed dreadful shafts at the ocean that flamed and pierced the waters, awakening mighty storms, distressing the nagas and the makaras of the sea, so that the god-hermits frequenting the sky cried out not to use another weapon for that one had done enough destruction, but the Ocean did not show himself, and Rama, threatened him again and set to his bow a Brahma arrow blest with a Brahma charm.

While Rama drew the bow in which a Brahma arrow was set, heaven and earth were darkened and the mountains trembled, lightning flashed, and all the creatures were afraid, and the mighty deep was wrought with violent movement. Then the Ocean rose from mid-sea like the rising sun. Jewelled and wreathed, he was decked with many gems, and followed by noble rivers like Ganga, Sindhu, and others. He appeared before Rama with joined palms and told him that every element possesses its own inherent qualities. So he also possessed the quality to be fathomless and hard to cross. He told Rama that neither for love nor fear could he block the movement of the waters, and then he told Rama that he could cross over the ocean by means of a bridge, and he promised to bear the weight of the bridge. He said that he would suffer it and hold it firm.

After hearing from Varuna that they could cross over it with the help of a bridge, Rama was appeased, but the Brahma arrow which he drew waited to find its mark and might not be restrained. Thus Rama inquired from the Ocean as to where the Brahma arrow should be sent, and then Varuna said that there was a part in his domain towards the north which was haunted by evil weights, and he requested Rama to let the Brahma arrow fall there. Then Rama let the flaming shaft fall on that place, and the water of the sea toward the north was dried and burnt, and the place became a desert. But with the blessings of Rama the desert became fruitful. Then the Ocean told Rama that there was a monkey known as Nala, who was the son of Lord Vishwakarma who had the skill of his father. He was full of energy, and would be able to construct the bridge across the ocean.

Once the Ocean provided complete information as to how the bridge should be constructed, it sank again beneath the waters. Then Nala told to Rama that the ocean spoke the truth and he hid his power since Rama did not ask him before about it. All the monkeys followed the orders of Nala and gathered rocks and trees and brought them from the forests to the shore, and set them in the sea. Some of the monkeys carried timber, some used the measuring rods, some carried stones; vast was the tumult and noise of crags and rocks thrown into the sea. On the first day of construction of the bridge, fourteen leagues were made, and on the fifth day the construction of the bridge was complete. The bridge was broad and elegant and firm and it looked like a line of parting of the hair on the head of the Ocean. Once the Adam`s bridge was constructed, the monkey host passed over, Rama and Lakshmana riding upon Sugriva and Angada. Some of the monkeys went along the causeway, while others plunged into the sea, and others coursed through the air, and the noise of the monkey army drowned the sound of the ocean waves.