The overall layout of the Indus is based on a grid of right angles. Large streets run in straight lines in north-south directions and are crossed by smaller streets in an east-west direction. The large streets were 33 feet wide and smaller streets ranged from 9 to 12 feet in length. The division of space into separate blocks is seen not only in the layout of the streets but also in house plans, the designs on pottery as well as the diagrams on seals. In contrast to this, the layout of early Mesopotamian cities was quite irregular. The idea of settlement planning was already well established before 2600 BC and is seen in all the settlements through the Indus. Each city is made up of a series of walled sectors or mounds with massive brick gateways. The orientation of the Indus cities along a north-south and east-west direction was probably linked to religious beliefs.
Well laid out streets and side lanes with drains are one of the outstanding features of the Indus cities, even in smaller towns and villages. The drains, made of brick, connected the baths and toilets of private houses to medium sized drains in the side streets. These flowed into larger drains in the main streets that were covered with brick and or stone blocks, which were removable for cleaning purposes. Corbelled arches were built to allow larger drains to cut beneath streets and buildings until they reached the city wall, throwing the water out onto the outlying plain. At regular intervals along the main sewage drains, were rectangular sump pits for collecting solid waste. These sump pits were cleaned on regular basis.
Wells and reservoirs were built within the cities to ensure drinking and bathing water. It has been estimated that Mohenjo-Daro may have had 700 wells, whereas Harappa may have had as few as 30. It could be because Mohenjo-Daro was far away from the Indus and had less winter rain. In Harappa, a large depression in the centre of the city indicates a reservoir that was accessible to many neighbor hoods. These 10-15 meter deep wells were lined with specially made wedge shaped bricks to for a solid cylinder that would not cave in with the pressure of the surrounding soil. At Mohenjo-Daro, most houses or blocks of houses had at least one private well and there were often public wells along the main streets for travelers and the general public.
In the Indus cities, there is a remarkable uniformity in both the raw materials and the style of construction. The most common material was sun dried bricks, baked bricks or stones. Doors and windows were made of wood. Floors were generally hard packed earth that was often replastered. Bathing areas and drains were made with baked bricks. Very few actual roofs have been discovered but they were probably of wooden beams covered with reeds and packed clay.
Most of the architecture from /Indus Valley civilization can be grouped into three categories: * Private houses:
They were built with rooms and central courtyard. Doorways and windows rarely opened out into the main streets but faced side lanes. The view into the house was blocked by a wall or hallway, so that the courtyard was private. Stairs led up to the roof or the second storey from one of the rooms or courtyard. Many houses were at least two storey high and some probably three storey judging from the thickness of the walls. Doors were made of wood; some were painted and possibly carved with a simple ornamentation. Windows had wooden shutters with latticework grills above and below them. In some houses large jars have been found which were probably used for storage purposes. Pottery vessels were sunk in some of...