Georg Gerster (b.1928) is a pioneer in aerial photography. For over 40 years he has taken breath-taking pictures of mountains, coasts and spectacular archeological sites in 111 countries on all continents. Based near Zurich, Switzerland, he also works as a journalist, and is a regular contributor to the Neue Zurcher Zeitung and National Geographic. Paul Cartledge (b.1947) is Professor of Greek History, the A G Leventis Professor of Greek Culture and a Fellow of Clare College, Cambridge. He also holds a visiting Global Distinguished Professorship at New York University. Cartledge is a world expert on Athens and Sparta in the Classical Age and was chief historical consultant for the BBC TV series 'The Greeks' and the Channel 4 series 'The Spartans'. His most recent books include 'Ancient Greek Political Thought in Practice' (2009) and 'Ancient Greece: A History in Eleven Cities' (2009). He is also an honorary citizen of (modern) Sparta.