The Iron Pillar
It was erected by Kumara Gupta of Gupta dynasty that ruled northern India in AD 320-540. According to the ancient records, it was present in Madhya Pradesh before it moved to Delhi. But by whom and when still remains a mystery. Along with this, the Iron Pillar has not rusted in all these years leaving everyone bewildered. The pillar thus, highlights ancient India's achievements in metallurgy. The pillar is made of 98 per cent wrought iron and has stood 1,600 years without rusting or decomposing.