A Mountain Lost

The Aravalli mountain range extends for more than 692 km from Champaner in Gujarat to Delhi and beyond. Its role in defining the shape of the Indian subcontinent and its climate, and the fact that it triggered the explosion of multicellular life, are under-appreciated. The rugged mountains guide the monsoon clouds and protect the fertile alluvial river valleys from the assault of cold westerly winds from Central Asia. However, over the past four decades, the world's oldest mountain range has been destroyed by mining, deforestation and over-exploitation of its fragile and ancient water channels

- Pranay Lal

IF YOU were an alien or a space traveller some three billion years ago (it is possible to imagine this in the current political climate), the only discernible feature you would have seen—which defined the northern margins of the landmass we call India—would have been the Aravalli mountain range. It took nearly two billion years (3.2 to 1.2 billion years ago) of shoving and pushing of tectonic plates and magma outpourings to create these oldest fold mountains in the world.

Since then, these mountains have endured millions of years of sustained assault of lava flows, submergence by seas, uplift by force of gushing magma from the depths of the Earth, collision with landmasses and erosion by wind and rain. But the Aravallis now struggle to survive the greed, pettiness and the extreme short-sightedness of politicians and corporations.

Starting from its south extent, the Aravallis begin their 692 km expanse from Champaner and Palanpur in Gujarat as small denuded hills. The peaks reach their maximum height in the south-western segment, with some rising more than 1,000 m (like the 1,722 m-high Guru Shikhar near Mount Abu and hills around Udaipur). As we move north, the range begins to taper and the hills become modest. By the time the Aravallis reach Delhi, they get inundated under a swathe of young alluvium, only rising occasionally as hillocks like the Raisina Hill, upon which rest the powerful government offices, the North and South Block. The northeastern part of the Aravallis upon which Delhi sits has an average elevation of 400-600 m.