Rama wanted a bridge to be built to link the mainland with Lanka. But for this the help of the sea-god, Varuna, was required.
When Varuna failed to answer his summons, Rama in great wrath swore he would scorch the seas and dry up the ocean. When he started doing so, the sea-god was humbled. He appeared on the crest of the waves and promised all his help for building the bridge.
Millions of vanaras were at work. They brought huge boulders from the hills and tall trees from the forests. Skilful workers laid them side-by-side and built a long powerful bridge across the sea, which would bear the weight of the army of vanaras and other creatures.
In great jubilation the vanaras crossed the bridge to Lanka. They camped within sight of the city in a region where there was plenty of fruits, wild roots and water.
The signs were auspicious for the Vanara army. There was great excitement everywhere at the approach of war with the rakshasas.
But the news that the vanaras had pitched camp in the shadow of the city worried Ravana.