The greater Indus region was home to the largest of the four ancient urban civilizations of Egypt, Mesopotamia, South Asia and China. It was not discovered until the 1920's.
"A long march preceded our arrival at Haripah, through jangal of the closest description. East of the village was an abundance of luxuriant grass, where, along with many others, I went to allow my nag to graze. When I joined the camp I found it in front of the village and ruinous brick castle."
"The real heroes of this story of the discovery of the Indus civilization were such individuals–a discerning archaeologist like Sahni and a brilliant one like Banerji, who had within a few years of each other uncovered the relics entombed in Harappa and Mohenjo-daro respectively."