The most interesting urban feature of Harappan civilization is its town-planning.
The uniformity is noticed in the lay-out of the towns, streets, structures, brick size, drains etc.
Almost all the major sites (Harappa, Mohenjodaro, Kalibangan and others), are divided into two parts–a citadel on higher mound on the western side and a lower town on the eastern side of the settlement.
The citadel contains large structures which might have functioned as administrative or ritual centres.
The residential buildings are built in the lower town.
The streets intersect each other at right angles in a crisscross pattern. It divides the city in several residential blocks.
The main street is connected by narrow lanes. The doors of the houses opened in these lanes and not the main streets.
The houses were largely built of burnt bricks.
The houses of common people, however, differed in size from a single-room house in Harappa to bigger structures.
The drainage system
The drainage system of the Harappans was elaborate and well laidout.
Every house had drains, which opened into the street drains.
These drains were covered with manholes bricks or stone slabs (which could be removed for cleaning) were constructed at regular intervals by the side of the streets for cleaning.
This shows that the people were well acquainted with the science of sanitation.
At Mohenjodaro the ‘Great Bath’ is the most important structure.
A thin layer of bitumen was applied to the bed of the Bath to ensure that water did not seep in.
The bath was surrounded by sets of rooms on sides for changing cloth.
Scholars believe that the ‘Great Bath’ was used for ritual bathing.
Another structure here located to the west of the ‘Great Bath’ is the granary.
It consists of several rectangular blocks of brick for storing grains.
A granary has also been found at Harappa. It has the rows of circular brick platforms, which were used for threshing grains.
At Lothal, a brick structure has been identified as a dockyard meant for berthing ships and handling cargo.
This suggests that Lothal was an important port and trading centre of the Harappan people.