1-153-638 - Ann Ronan Picture Library/Heritage-Images

The Pharos of Alexandria, 18th century. One of the Seven Wonders of the Ancient World, the Pharos of Alexandria was a lighthouse built by Sostratus of Cnidus in 280 BC on the island of Pharos in the bay of Alexandria, Egypt. The lighthouse operated by means of a mirror to reflect sunlight during the day, and a fire lit at the top of the tower at night. It remained operational until it was largely destroyed by earthquakes in the 14th century.