The Classical WorldTechnology Iron Pillar of Delhi c. 400 CENotable A seven-meter wrought iron pillar from the Gupta era has resisted rust for 1,600 years. It shows the skill of ancient Indian ironworkers. ▲ MattersSaveShareTrace roots Longest chain: The Big Bang → First stars ignite → Supernovae seed heavy elements → The Sun forms → Earth forms → First oceans → First life → Photosynthesis evolves → Great Oxidation Event → Complex cells (eukaryotes) → Multicellular life → First animals → Cambrian Explosion → First vertebrates → Jawed fish → Fish walk onto land → The amniotic egg → The Great Dying → Dinosaurs appear → Asteroid ends the dinosaurs → Early primates → Apes split from monkeys → Human line splits from chimpanzees → Walking upright → First stone tools → Genus Homo appears → Homo erectus → Control of fire → Habitual fire and cooking → Homo sapiens appears → Complex language → Natufian villages → Oldest known bread → Agriculture begins → Irrigation → Uruk and the first cities → Cylinder seals → Writing (cuneiform) → Babylonian mathematics → Babylonian astronomical diaries → Thales and natural philosophy → Trial and death of Socrates → Plato's Academy → Aristotle's Lyceum → Alexander's conquests → Maurya Empire → Gupta Empire → Iron Pillar of Delhi Community notesLoading notes… Learn more ranked by votesBookR. BalasubramaniamDelhi Iron Pillar: New Insights ↗Editor's pickVideoSearch on YouTubeDelhi iron pillar rust mystery ↗Editor's pick