A Greco-Roman scholar, most famous for the three works he produced on astronomy, geography and astrology. Almost nothing is known of Ptolemy’s life except that he lived in Alexandria, and was a Roman citizen. His first book, the ‘Almagest’ was an astronomical text based on a theory of a geocentric universe. This was followed by its companion, the ‘Tetra-Biblos’, which concerned astrology and the effects of the planets and stars on human health and behaviour. Ptolemy wrote his most famous work, the ‘Geographia’ around 150CE, using an atlas by Marinus of Tyre and adding information from Roman, Persian and Babylonian sources. The importance of this work for generations of map-makers, cartographers and navigators cannot be over-stated. Interesting, no examples of a map by Ptolemy himself, if any, has survived.