The origin of the remarkable Iron Pillar, part of the world-heritage-listed Qutub funerary complex in India’s Delhi, is lost to time. All sorts of ideas have been put forward over the decades.

New Delhi’s Iron Pillar has long fascinated scientists both at home and abroad. But it wasn’t until 2003 that experts cracked the metallurgical mystery behind this unusual attraction.

Made of iron, the Iron Pillar at Mehrauli has not rusted for over 1,600 years despite exposure to the elements, showcasing India’s advanced metallurgy techniques.