Pharos Alexandriae

About

One of the Seven Wonders of the Ancient World; construction begun under Ptolemy I Soter, completed under Ptolemy II Philadelphus (traditionally dated 247/246 BCE), on the island of Pharos at the harbor mouth. Described in detail by Pliny (who gives its architect, Sostratus of Cnidus) and Strabo. Still standing and functioning as an active lighthouse throughout the Roman imperial period at the 117 CE snapshot; it survived until a series of medieval earthquakes felled it between the 11th and 14th centuries CE (long after our snapshot). Point is the traditional site, now occupied by the 15th-century Qaitbay Citadel.

What happened here

The fire burns at the top all night and is visible for miles from a coastline that otherwise gives a pilot nothing to steer by. Fuel — wood, or oil where wood is scarce — is carried up an internal ramp or hoisted, and a crew lives on site to keep the fire fed and the reflecting surfaces clean. A tower on a mole doubles as a harbour marker and a breakwater. Mariners complain that a steady light at sea can be mistaken for a low star, and that is a real hazard. By day the tower is a landmark instead. It appears on coins and on the mosaics of shipping agents, because a port with a lighthouse is advertising that it can be entered at night.

In ancient writing

• Strabo, Geography 17.1.6

  A white marble tower of many storeys on the island's tip, given by Sostratus of Cnidus for the safety of sailors on a coast with no landmarks and dangerous shoals.

• Pliny the Elder, Natural History 36.83

  Puts the cost at 800 talents and worries that a fire burning steadily at sea can be mistaken for a star.

Sources

• Pliny NH 36.83
• Strabo Geography 17.1.6
• https://www.worldhistory.org/Lighthouse_of_Alexandria/