Which of the following physiographic divisions of India is characterized by the presence of longitudinal valleys known as 'duns', such as Dehra Dun, lying between the Lesser Himalayas and the Shiwalik range?

💡 Solution & Explanation

The Shiwalik range, representing the outermost foothill belt of the Himalayas, is separated from the Lesser Himalayas (Himachal) by flat-bottomed longitudinal structural valleys filled with detrital gravel and alluvium, locally known as duns. The Himadri refers to the Great Himalayan range containing towering peaks exceeding six thousand meters. The Bhabar is a narrow, porous gravel belt lying immediately along the foothills where streams disappear underground into coarse alluvial debris. Dehra Dun is the most prominent of these longitudinal valleys in Uttarakhand.