Here, to the north of the citadel, lay the workmen’s quarter, their working platform, and a granary the entire complex suggesting a high degree of regimentation of their population.
Important Harappan cities, such as Mohenjodaro, Harappa, Kalibangan, Dholavira and Surkotada, were divided into two parts – a fortified settlement on the high mounds designated as ‘citadels’ and the main residential areas to the west of it called ‘lower town’.Nowhere was a building allowed to encroach on a public highway as in Sumer. At Mohenjodaro each lane had a public well, and most of the houses had a private well and bath. Inside this square or oblong, the area is intersected by a number of narrow lanes crowded with houses. They intersected at right angles dividing the city into square or rectangular blocks. Streets varied from 9 feet to 34 feet in width and ran straight sometimes as far as half a mile.One finds the streets and lanes lay out according to a set plan: the main streets running from north to south and the cross-streets and lanes running at right angles to them. The basic layout of large Harappan cities and towns shows a regular orientation. The most striking feature of Harappan civilization was its town-planning.
Town-Planning, Public building and Drainage of Harappan Civilization