85% of the world's sandstone is quarried in Rajasthan, and the Bundi Highway cuts through this stone-quarrying region like a knife. There is a stretch of this highway where, for 20km, all you can see in every direction are quarries and mining activity!
Quarrying stone is intrusive, heavy, labour-intensive and dirty, generating incredible volumes of waste. Some of the waste is simply spoil, of no value; it must be removed to allow access to the valuable material that lies underneath. This spoil is dumped in vast piles that, from a distance, could easily be mistaken for beautiful mountain ranges...sadly they are not.