The collapse of Polonnaruva marked the end of the lowland kingdoms in Sri Lanka's arid north, and the end of a distinctive and successful form of hydraulic low-density urban settlement.

Although historically understood as the result of Indian invasion, recent research at Anuradhapura has suggested the very economic system that enabled these kingdoms to flourish within a marginal environment, may have facilitated their collapse.

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Recorded 3 June, 2019.