Since the beginning of the historical era, man has been building dams. The ancient civilisations of Sumeria, Babylonia, Egypt, Ceylon and Cambodia, for example, were all justifiably famed for their irrigation works: indeed, the bunds and tanks which remain at such ancient capitals as Anuradhapura in Sri Lanka, or Angkor Watt in Cambodia, still survive to bear proud witness to the engineering skills of those who constructed them.