What happened to Indus valley?

1. Natural Causes:

- Droughts: Prolonged droughts could have led to water shortages, agricultural failure, and a decline in the population.

- Flooding: The region experienced frequent flooding, especially in the lower Indus and Ghaggar-Hakra plains. Extensive flooding might have disrupted settlements, damaged infrastructure, and affected agriculture.

- Climate Change: Over time, there could have been significant shifts in climate patterns, leading to changes in vegetation and water resources, which could have stressed the civilization's adaptability and resilience.

2. Internal Factors:

- Urban Decay: Some argue that the cities declined due to poor urban planning, overcrowding, and inadequate sanitation, which could have led to health issues, epidemics, and social unrest.

- Overexploitation of Resources: Overgrazing, deforestation, and unsustainable agriculture could have depleted natural resources and decreased the region's carrying capacity.

- Collapse of Trade Networks: The Indus Valley civilization depended on trade with neighboring regions for essential resources. Disruptions in these trade routes might have caused shortages and economic instability.

- Social Inequalities: The civilization may have experienced internal conflicts, class struggles, or power struggles, which could have contributed to its downfall.

3. External Factors:

- Invasions: While there is evidence of defensive structures, there is ongoing debate about whether the civilization faced widespread invasions or raids by external groups like the Aryans.

Combination of Factors:

It is likely a combination of several factors that caused the decline of the Indus Valley civilization, rather than a single definitive reason. The interplay of natural disasters, internal weaknesses, and external pressures could have contributed to its eventual collapse.