Which dynasty ruled Egypt when construction of the Lighthouse of Alexandria began?

Construction of the Lighthouse of Alexandria began under the Ptolemaic dynasty.

The Ptolemies ruled Egypt after the death of Alexander the Great and established Alexandria as a major centre of government, trade and scholarship. The lighthouse was begun during the reign of Ptolemy I Soter and completed during the reign of his son, Ptolemy II Philadelphus, in the early third century BC.

The project reflected the dynasty’s interest in presenting Alexandria as a powerful capital with an impressive harbor. The tower on Pharos helped ships navigate toward the port and also advertised the city’s wealth and engineering skill.

Later writers associated the monument with the architect Sostratus of Cnidus, although the precise wording of the dedication and the extent of his role are debated. The building survived for many centuries before earthquakes caused severe damage.