The city-state prospered through its maritime affairs, evidenced by the remains of monumental buildings and artwork. The treaty with Polyrrhenia gives evidence that in the third century BC the inhabitants of Phalasarna were engaged in piracy, a common practice of the Cretan city-states. In 69-67 BC the Romans sent forces to eliminate piracy from the eastern Mediterranean, stormed Phalasarna, blocked its harbor with massive masonry, and destroyed the whole city, probably killing its citizens. No ancient sources testify directly to these events, but evidence of burning and the harbor blockage itself suggest the tentative conclusions of the excavators.