Harappa is in Punjab, Pakistan; Mohenjo-daro is in Sindh, Pakistan. Dholavira and Lothal are in Gujarat, India. Rakhigarhi is in Haryana and Kalibangan in Rajasthan. Use these locations to understand the civilisation’s spread, not to draw modern borders around an ancient society.

Smaller settlements and farming villages also matter. They supplied food, materials and routes of contact. A map with a few famous city labels leaves out many places; it does not show that all the empty-looking spaces were uninhabited.

Crop remains indicate foods such as wheat, barley, pulses and some millets; evidence differs by site and period. Animal and fish bones add information about diet. A clay plough model suggests knowledge of ploughing, but the model is not itself a full-size farming tool.

Scientific studies of pots can identify traces of earlier contents, including dairy products in some findings. A trace at one site does not prove every Harappan ate the same meal. Cotton evidence concerns fibres and clothing, not a food crop. Cities depended on farming communities for regular supplies.

Drier conditions and changes in river systems could affect crops, water supplies and transport. Cities depended on those systems, so stress could encourage people to move or live in smaller settlements. These are linked explanations, not proof of one event causing every city to fall on the same day.

The textbook emphasises environmental factors. Scholars continue to examine regional differences and other causes. Some technologies and cultural practices survived. We should not claim that absence of a clear invasion explanation proves there was never any conflict anywhere.