Purvanchal Hills: Ranges of Northeast India on Map

Purvanchal Hills are the eastern extension of the Himalayas that form the hilly region of Northeast India. These hills are found in Arunachal Pradesh, Nagaland, Manipur, Mizoram, Tripura, and Meghalaya.

In this article, we will understand the location, formation, and major hill ranges of the Purvanchal region. Each range – including the Dafla, Abor, Miri, Mishmi Hills of Arunachal Pradesh, Patkai, Naga, Manipur Hills, Garo, Khasi, Jaintia Hills of Meghalaya, Mizo (Lushai) Hills, and the Mikir–Rengma–North Cachar Hills of Assam – will be covered in separate detailed articles linked from this page.

Location and Extent

Purvanchal Hills extend from the Patkai Hills of Arunachal Pradesh in the north to the Mizo (Lushai) Hills in the south. They form a natural frontier between India and Myanmar, covering parts of Arunachal Pradesh, Nagaland, Manipur, Mizoram, Meghalaya, Tripura, and southern Assam. The arc bends southwards from the eastern end of the Himalayas near the Dibang Valley and continues till the Chittagong Hill Tracts in Bangladesh.

• Latitude: roughly between 23°N to 28°N
• Longitude: between 92°E to 97°E
• Length: about 800 km (from Arunachal to Mizoram)

Formation and Geological Structure

Purvanchal Hills were formed when the Indian Plate collided with the Burmese Plate, causing the eastern edge of the Himalayas to bend and fold sharply towards the south. This bending created a series of parallel hill ranges separated by deep valleys.

Unlike the steep, snow-covered peaks of the western Himalayas, the Purvanchal Hills are low, rounded, and covered with thick forests. Most of the rocks here are sedimentary, deposited by ancient rivers and compressed over millions of years.

Major Hill Ranges of Purvanchal

Purvanchal includes several important hill ranges, which we will cover in separate articles. Here’s a brief overview:

1. Dafla, Abor, Miri, and Mishmi Hills – form the outer eastern Himalayan ranges in Arunachal Pradesh. These hills are the northernmost extension and connect directly with the eastern Himalayas.
2. Patkai, Naga, and Manipur Hills – form the frontier highlands along the Indo-Myanmar border. The famous Pangsau Pass lies in this region.
3. Garo, Khasi, and Jaintia Hills – together form the Meghalaya Plateau, an ancient part of the Indian peninsular block that was uplifted by tectonic movements.
4. Mizo (Lushai) Hills – mark the southern end of the Purvanchal arc and continue into the Chittagong Hill Tracts of Bangladesh.
5. Mikir, Rengma, and North Cachar Hills – are isolated hill systems of Assam, separated from the main Purvanchal chain but still part of its geological family.

Rivers in Purvanchal Hills

Many rivers of Northeast India rise from the Purvanchal Hills and flow through deep valleys before joining the Brahmaputra and Barak river systems.

• The Dihang, Dibang, and Lohit rivers originate in Arunachal Pradesh in the Mishmi and Abor Hills and together form the Brahmaputra in Assam.
• The Barak River, rising from the Manipur Hills, flows westward into Assam and later enters Bangladesh.
• The Tlawng, Tuirial, and Tuivawl rivers start from the Mizo Hills and join the Barak River.
• Small streams like Umiam, Umngot, and Kynshi flow from the Khasi and Jaintia Hills and form beautiful waterfalls before entering Bangladesh.
• The Dhansiri and Kopili rivers rise from the North Cachar and Mikir Hills and meet the Brahmaputra in Assam.