world greatest civilisation once developed in india in harrapa and mohamjodaro but what was the reason that it went down. harrapa civilisation had about 2 lakh people living there, on the other hand mohonjodaro was even more larger with a more number of people living there . they were highly developed. this fact can be deduced from the fact that when pyramids were being build at that time harrapa was already a developed and organised city. the question is still then why India declined to present status. pre-harrapan civilization ha...