Did you know that near the Qutub Minar in Delhi Stands an iron pillar which is more than 7 meters high.it weighs more than 6000kg.But the thing  that the pillar was made more than 1600 years ago and after such long time it has not rusted! For its quality of rust - resistance it has been examined by scientists from all the parts of the world! It tells something about the advances India had made in metal technology as back as 1600 years ago!!! 

This felt crazy for me, what about you :D