Ancient India developed diverse methods to harvest water, including 'guls' or 'kuls' in the Western Himalayas for agriculture, rooftop rainwater harvesting in Rajasthan for drinking water, inundation channels in Bengal's flood plains for irrigation, and structures like 'khadins' and 'Johads' in Rajasthan for rain-fed storage. These methods were designed to suit specific regional needs and environmental conditions.