Temple of Poseidon
About
Strabo described the Poseidium as a temple projecting like an elbow from the Emporium into the Great Harbor, a sacred landmark for ships entering port. Mark Antony built his retreat, the Timonium, right beside it after his defeat at Actium in 31 BCE. Priests here blessed the merchant fleets carrying Alexandria's grain toward Rome. The temple still marked the harbor entrance when Trajan's fleet sailed for the Parthian campaign.
What happened here
The building itself is a house for the god, and most people never go inside. Everything public happens on the steps and at the altar in front: an animal led up, examined, killed cleanly, its organs read, the meat divided and eaten. The priest covers his head and a flute player keeps up a noise so no ill-omened word is heard. Worshippers leave what they can afford — a terracotta figure, a coin, a model of the body part they want healed — and the accumulated clutter is periodically cleared and buried on site. On festival days the doors are opened and the cult statue is dressed, garlanded, and sometimes carried out through the streets. The temple also holds money, which is why towns keep their treasury in one.
In ancient writing
- Strabo, Geography 17.1.9
Describes the Poseidium as a temple on a promontory projecting from the Emporium into the harbor.
Sources
Nearby
Roman Maps shows the empire frozen at 11 August 117 CE, the day Trajan died — its moment of greatest territorial extent. Explore the full map →


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