Columns of Hercules
Two large pyramidal columns set up by the Phoenicians as lighthouses and landmarks, dedicated, one to Hercules (the sun), and the other to Astarte (the moon).
By the Greeks and Romans the two pyramidal mountains at the Straits of Gibraltar (Calpe and Abyla), the former in Europe and the latter in Africa, were termed the Pillars of Hercules.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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