Explanation:

The Pamir Mountains, or the Pamirs, are a mountain range in Central Asia at the junction of the Himalayas with the Tian Shan, Karakoram, Kunlun, Hindu Kush, Suleman and Hindu Raj ranges. They are among the world’s highest mountains.
The Pamir or popularly known as the roof of the world is the connecting link between the Himalayas and the high ranges of the Central Asia.
To the north they join the Tian Shan mountains along the Alay Valley of Kyrgyzstan. To the south they border the Hindu Kush mountains along Afghanistan's Wakhan Corridor.
Maximum development of glaciers occurs in the Karakoram range. This range accounts for about 16,000 sq km or about half of the snow bound area of the Himalayan region.
Purvachal or the Eastern hills and mountains are part of the Himalayan mountain system having their general alignment from the north to the south direction.
The Purvachal comprises the Patkai hills, the Naga hills, Manipur hills and the Mizo hills.