Iron pillar of Delhi
A six-tonne iron pillar that has not rusted in 1,600 years
This seven-metre pillar weighing over six tonnes was forged under the Gupta king Chandragupta II. It has barely rusted: its high-phosphorus iron grew a protective film that in 1,600 years has thickened by just one-twentieth of a millimetre.
Wikipedia (Russian) · Wikipedia (English) · 5th century
Did you know
In 1969 Erich von Däniken cited Delhi's rustless iron pillar as evidence of alien visitors. The answer is earthly: the ancient iron is rich in phosphorus, which grew a thin protective film of iron phosphate. Share →
Meanwhile around the world (±25 years)
Europe
- 395 Division of the Roman Empire — 7 years earlier
- 410 Sack of Rome by the Visigoths — 8 years later
Middle East
- c. 405 Mesrop Mashtots creates the Armenian alphabet — 3 years later
Africa
- c. 397–400 Augustine's Confessions — 5 years earlier
Alive at the time
- Augustine of Hippo (aged 48)
- Hypatia (aged 42)