Indus River Valley Civilization

Less is known about this River Valley Civilization because we have less ruins to interpret. The written language has yet to be deciphered. The first great finds--Harappa in 1921 and Mohenjo-daro a year later--brought to light a society impressive for its uniformity. In each city, a raised "palace" area was set off from a rectilinear "middle town" and from less well-developed residences even farther out. Streets were not only drawn on a north-south grid, but were of fixed width--around 9 m for the main thoroughfares, 1.5 m and 3 m for the lanes on which most houses opened. The dimensions of the fired bricks used in palaces, houses and the revetments of heavy fortifications--nearly 14 m wide at their base in Harappa--followed a strict geometric ratio, 1x2x4.

The ruins of Mohenjo-daro indicate a civilization with advanced technical skills. The streets were lined with drainage gutters and it appeared that many of the houses were linked by these gutters. These have been labeled by archeologists as sewage lines. Mohenjo-daro had the first sophisticated waste removal systems city wide.