Most Indus Valley cities were made from mud bricks. First the brick-makers mixed soil, clay and water to make squishy mud. Next they squashed the mud into a wooden mould which was the shape of a brick. And then they turned out the mud-brick, like you would turn out a sand-castle.
Mud-bricks could dry in the hot sun. But it was better to put them inside a kiln. The fire in the kiln heated or 'fired' the bricks at a high temperature to make them very hard.
All Indus Valley bricks were the same ratio of 1 : 2 : 4 but came in different sizes. A common size was 7 cm high x 14 cm wide x 28 cm long. Bricks were laid in rows or 'courses', end to end and crossways, using wet mud as cement to stick the bricks together. Indus Valley walls were so strong that many have stood for over 4,000 years!
Indus Valley cities were neatly planned. They had straight roads making a grid pattern, dividing the city into blocks. Main streets were almost 10 metres wide, so two bullock carts could pass by each other. Drains were laid along the streets and wells were dug for water.
Mohenjo-Daro stood on a mound and had a wall with gateways to go in and out. Some city districts inside were raised on mounds too. On the highest mound was a citadel, which was perhaps where priests and rulers lived.
People built new houses on top of old ones, as the mud-bricks crumbled. So, over hundreds of years the cities grew higher. In time some new houses were seven metres above the level of the old houses at the bottom!
Mohenjo-Daro's Great Bath
The Great Bath in the city of Mohenjo-Daro looks like a swimming pool. It was over 14 metres long and seven metres wide. It had a brick-paved courtyard and columns on three sides.
Water (probably from a well) filled the Bath to about 2.4 metres deep (a tall man is about 1.8 metres). Two sets of steps led down to the bottom. Water drained out through one corner into a drain. Tar and gypsum mortar between the bricks made sure no water leaked out.
Water was very important to the Indus Valley people. The Great Bath may have been a temple, where priests and rulers bathed in religious ceremonies.
Tools and jobs
Indus Valley people used some tools like the ones we use today - hammers, knives, needles, fish-hooks, axes, razors and saws. But many Indus tools were made of stone called flint. The metal Indus Valley people used most was copper. They made sharp copper tools. They mixed copper and tin to make bronze.
Workers did different jobs. For example, some workers made stone querns (for grinding grain to make flour). Others spun and wove cotton into clothes and cotton bags. City workers made beads, fishing nets, pots, baskets...everything people needed. Children learned work- skills from their families.
Indus Valley people had clean water and excellent drains - better than any other ancient civilisation. Most city homes had a bathroom and toilet, connected to the city drains. Some people had private wells, for clean water. Others went to public wells, to fetch water in jars or animal- skin bags.
Waste water flowed out of the house through pipes into the street-drains. 'Poo-cleaners' cleaned the drains and emptied the pits where sewage from toilets collected.