If you're expecting to be attacked and besieged, as all these citadels would be by an invader, you would want more than anything else a water supply, but they didn't necessarily have good water supplies in such circumstances.

如果你预料到会被攻击和包围,就像这些城邦面对侵略者那样,你最关心的一定是水源供应,但在这样的情况下,他们未必能找到充足的水源

耶鲁公开课 - 古希腊历史简介课程节选