A map of Alexandria in 280 BC. Note the Pharos Lighthouse built by Ptolemy II Philadelphos. The beacon of the 150 metre (492ft) tower was crowned by a statue of Poseiden and could apparently be seen from a vast distance out to sea, which indicates that the Alexandrians may have known of the lens or mirror as used in modern lighthouses.
Location: Alexandria Egypt
Photographer: Clive M Fox