Pharos was a small island just off the coast of Egypt which, with its artificial connection to the mainland (the Heptastadion) formed one side of the harbour of Alexandria. As the landscape in the area was very flat and lacking in the kind of landmark used at the time for navigation, a marker of some sort at the mouth of the harbour was deemed necessary. The lighthouse was built by Sostratus of Cnidus in the 3rd century B.C., the project having been initiated by the first Hellenistic ruler of Egypt, Ptolemy Soter.
With the exception of the Great Pyramid of Giza, the lighthouse lasted the longest of the Seven Wonders. It was severely damaged by two earthquakes in 1303 and 1323, to the point that the Arab traveller Ibn Battuta reported not being able to enter the ruin. Even the stubby remnant disappeared in 1480, when the then-Sultan of Egypt, Qaitbay, used the rubble to help build a fort at a nearby location.