Airāvata Varsha is the northernmost varsha (region) of Jambū Dvīpa. It lies beyond the Śṛṅgavān mountain and borders the Kshīra Sāgara, the Ocean of Milk. The Bhīshma Parva of the Mahābhārata calls it the best of all the varshas. The sun does not burn there, old age does not come, moonlight fills every direction, and the people have the beauty of the lotus and live for thirteen thousand years.

Location

Airāvata Varsha lies north of the Śṛṅgavān mountain and reaches to the shore of the Kshīra Sāgara (Milk Ocean). In the south is Bhārata Varsha. Sañjaya says the two are like the two ends of a bow. Between them lie five varshas: Śveta, Hiraṇyaka, Ilāvṛta, Hari Varsha and Haimavata.

Why it is the best varsha

Sañjaya says plainly that Airāvata Varsha is better than every other varsha:

anya varshamulakantē uttamamainadi.

This means: it is the best, better than the other varshas. Its qualities are these.

No heat of the sun. The burning rays of the sun do not reach it.
No old age. The people never grow old.
Moonlight in every direction. The whole varsha is bathed in cool moonlight.
No hunger, thirst or tiredness. The people never feel them.
No sweat. Their bodies do not sweat, and their own fragrance is pleasant.
No rajas. The varsha is completely free from rajas, the quality of restlessness.

The people of Airāvata

The people are described with the picture of the lotus.

Their skin has the glow of the lotus (kamala kānti).
Their colour is the colour of the lotus (kamala varṇamu).
Their wide eyes are shaped like lotus petals (kamala patra-nayanas).
Their bodies carry the scent of the lotus.

They are beings who came down from svarga (heaven) after using up most of their puṇya (merit). They live out the rest of their good karma in this most comfortable of varshas. They live for thirteen thousand years.

Bhagavān Vishṇu on the shore of the Kshīra Sāgara

On the northern shore of the Kshīra Sāgara, where it meets Airāvata Varsha, Bhagavān Vishṇu lives on a golden chariot (suvarṇa ratha). The chariot is described like this.

It has eight wheels.
It moves at the speed of thought (mano-vega).
It is filled with all beings (samasta bhūtalalu kūḍukoṇi).
It shines with the brightness of fire.
It is adorned with Jāmbūnada gold.

This is told where the text speaks of Bhagavān Vishṇu as the one who spreads out and draws in all creatures:

sama sta prāṇulanu vistariṃpajēyucu saṃkocinpacēyucu nunḍunu.

This means: He keeps spreading out and drawing in all living beings.

Svayamprabhā Śāṇḍilī Devī on Śṛṅgavān

The Śṛṅgavān mountain has its northern side towards Airāvata. On its three peaks lives the devī Svayamprabhā Śāṇḍilī Devī.

Sources

Mahābhārata, Bhīshma Parva, Chapter 8