Strait of Hormuz
The Strait of Hormuz lies at the entrance to the Persian Gulf, which today has an average depth of just 35 metres. During the last Ice Age it has been shown the Persian Gulf was a completely dry basin and possibly the home of a pre-historic civilisation. This idea has been developed by Dr. Jeffrey Rose of the University of Birmingham(a).
One of the more unusual suggested locations for Atlantis is Mesopotamia, the equivalent of modern Iraq. Understandably, this led to the Strait of Hormuz being identified as the Pillars of Heracles.