The cities were divided into two parts. The upper part called ‘citadel’ was built on a raised ground. It was inhabited by the upper class and had public buildings such as granaries. The lower part was inhabited by the common people. Each house had a courtyard, several rooms around it, a toilet and a well. All the buildings were built of burnt bricks. Large blocks of houses were built along both the sides of streets.The roads were wide and straight and cut each other at right angles. Smaller streets led to bigger streets. The streets had lamp posts. The drainage system was of the highest order ; even many of our present towns do not have such excellent drainage system. House drains were connected to the street drains which joined the main drains which emptied outside the city limits. The drains were covered with stone slabs and had manholes at regular intervals. They were cleaned regularly.The Indus people were veiy conscious of hygiene and sanitation.
